The nuclear option: Voting for the pan-European party Volt

Abstract

Volt is a pan-European, Eurofederalist party that seeks to deepen and democratize European Union integration. It participated in elections in nine European countries and won representation in the Dutch Parliament and German constituency for the European Parliament. We examine Volt Netherlands, which studies the possibilities of a pan-European party. We look at the importance of its pro-European positions for voting for this party; this is an issue that all national branches of Volt share. We also examine the specific political opportunity structure of the Netherlands, where pro-nuclear environmentalism was an open niche. In this way, we weigh the importance of the party's pan-European appeal and the country-specific political opportunity structure. We show the importance of the country-specific factors for new party support and thus cast doubt on the ability of pan-European parties to mobilize voters all over Europe with the same message.

Keywords

Political parties at the European level voting behaviour EU integration dimension nuclear energy new political parties

Introduction

In the wake of Brexit, a new pan-European party was founded: Volt. What set this party apart from the other parties in the European Union (EU) was not necessarily its social-liberal, environmentalist and pro-European agenda but rather its organization: where other political parties in Europe are organized primarily as national parties that can work together in a European federation of national parties (called ‘party at the European level’ formally and ‘Europarties’ informally), Volt is a pan-European party that has national branches (Kolster and Homeyer, 2019; Leruth, 2021; Lefkofridi, 2020). These national branches see different levels of success. The German branch won a single seat in the European Parliament in 2019, the Dutch branch won three seats in the lower house of the Dutch parliament in 2021 and, in the same year, the Bulgarian branch won two seats in the Bulgarian parliament as part of an electoral coalition.

The central question of this article is under what conditions do voters vote for Volt? Is the pro-European profile of this party a major part of its attraction? Or does it appeal to specific national constituencies based on a specific national profile? In other words, is the pan-European nature of the party an electoral advantage of the party? Or does it appeal to specific national electorates with specific messages, like members of other European political families?

This study examines the Dutch voters for Volt. As is detailed below, the Dutch case provides a crucial case to study Volt for one because it has been most successful (winning national representation on its own), but also because it provides enough information for systematic study. This does not mean to say that this electorally most successful branch of the party is representative or that we expect the patterns we find here to be valid for Volt in other countries. Yet, by understanding whether the drivers of its success are related to its pan-European manifesto or to a national political opportunity structure, we can get a grasp of under what circumstances Volt can be successful in other countries.

This article speaks to a number of different literatures. Firstly, the literature on new party formation. One of the ways in which new parties develop is ‘branching’, where the impetus for organization comes from a transnational party that decides to organize itself in a new country (Krouwel and Lucardie, 2008). While there is an extensive literature on new party success (Van De Wardt and Otjes, 2022), we know little about whether this kind of branching strategy is electorally successful. By studying the success of one national Volt branch, we can get a grasp on this.

This article also speaks to the literature on political parties at the European level (Day, 2005; Herter, 2013; Hix, 2002; Holmes and Lightfoot, 2013; Poguntke et al., 2007; Johanson, 2009; Johanson and Raunio, 2019). While the development has mostly been top-down (Johansson and Raunio, 2005), Volt's model of a pan-European party was developed bottom-up. This article answers the question of whether this kind of new pan-European party model offers a viable alternative for the existing political parties at the European level.

In this article, we examine which voters voted for Volt in 2021. We ground our expectations in the literature on new parties and political parties at the European level and develop two expectations. The first is based on the ambition of Volt to be a pan-European party with a common pro-European manifesto. Therefore, we propose the EU integration hypothesis which, holds that the pro-European voters support the party. The second is based on the specific political opportunity structure in the Dutch 2021 elections. As we argue in greater detail below, pro-nuclear environmentalism was a specific niche for Volt Netherlands in the 2021 election. Therefore, we propose the pro-nuclear environmentalism hypothesis that holds that Volt attracted voters that favoured both climate action and nuclear power. This is curious to say the least because Volt Europe is not in favour of nuclear energy. We test these expectations using two samples of the Dutch 2021 electorate. Analyses of both samples show the importance of the specific political opportunity structure in the Netherlands and cast doubt on the possibilities of Volt to mobilize voters on the basis of a pan-European agenda.

When do voters vote for new parties?

One can think of Volt as a ‘normal’ new party. The electoral support for new parties has been subject to ample academic attention. In addition to elements of the political system, such as a proportional electoral system (Tavits, 2008), the interplay between political demand and supply plays an important role in generating electoral support for new parties (Van De Wardt and Otjes, 2022). The political opportunity structure is an important factor in the electoral success of new parties (Kitschelt, 1988; Rydgren, 2004; Nachtwey and Spier, 2007; Fell, 2006; Spies and Franzmann, 2011; Abedi, 2002; Arzheimer and Carter, 2006). The core notion here is that new parties get support from voters in specific niches in the political space.

One way to think of these niches is that they develop when established parties move on the established left-right dimension, leaving some previously occupied positions open and a set of voters politically homeless (Van De Wardt et al., 2017; Spoon and Klüver, 2019). This is essentially an extension of the classical Downsian approach to voting (Downs, 1957): people vote for the closest party, and when the established parties are all distant, a new party may be closest to them. To understand why voters cast their vote for new parties, a dynamic and multidimensional approach to the political space is often useful (De Vries and Hobolt, 2020; Meguid, 2005): new parties can benefit electorally from the politicization of new issues. As these issues become politicized, new lines of conflict develop. On these new issues, established parties may leave open new niches in the political landscape. That is there are new combinations of issue positions where there is a cluster of voters, but no political party to represent them. New parties can win the support of voters in these open political niches. It is important to note here that while political scientists tend to use a low-dimensional model to understand the political space in general terms (two dimensions being common) for specific smaller parties, other lines of conflict may matter.

The appeal of pan-European parties

Volt is not a normal new party, but a pan-European party. As Niedermayer (1983) proposed, this is a specific stage in the development of parties in Europe. He envisioned party-political cooperation in Europe going through three phases. Firstly, national parties coordinate transnational issues with parties in other European countries. This is indeed how European political parties first developed: they were loose confederations of like-minded parties, European offshoots of the Socialist and Liberal International, linked to the party groups in the European Parliament (Van Oudenhoven, 1965). Next, the cooperation between parties would be embedded in a permanent transnational European party organization. Indeed, in the 1970s, they formed more structured federations with a permanent bureau in Brussels (Hix and Lord, 1997). As of 2022, ten of these are recognized by the EU (Kolster and Homeyer, 2019).¹ In the final phase of Niedermayer's model, the autonomy of national member parties would be limited in favour of the transnational party. Decisions would be made by pan-European majorities without national vetoes; individual citizens would join them instead of national parties; the European party has the last say about the program, the course and who runs for the party (Ladrech, 2002); and the European programme is extensive and binding for all branches.

The notion of these pan-European parties is closely related to the idea of transnational political space in the EU, which is a common political space in all EU member states. Empirical studies of party competition so far have shown that a common transnational party space does not exist (Huijsmans and Krouwel, 2021): the issue of EU integration, for instance, is interpreted very differently by parties across the EU. It also does not appear to be the case that party spaces are becoming more similar: both the Eurocrisis and migration crisis had asymmetric impact across European party systems. Such cross-national different interpretations of EU integration and variation in how EU issues relate to other salient political dimensions make it difficult for any transnational party to represent voter groups across a large number of member states. Andeweg (1995) and Habermas (2015) argue that such a transnational political space can only develop if only pan-European parties contest in elections, while Von Achenbach (2017) already sees a common transnational political space in the European Parliament, dominated by the Europarties, stuck in the second phase.

Despite their increasing embeddedness in EU law, the existing parties at the European level never reached this third phase. A European political party ‘is not a homogeneous organization, but a reticular conglomerate’ of the European Parliament group, national parties and a weak EU-level extra-parliamentary organization (Voerman, 2009). These are coalitions of parties that run in specific national contexts with a lowest common denominator manifesto and no control over who runs in these elections (Kolster and Homeyer, 2019; Ladrech, 2006). National parties serve as gatekeepers of transnational party activity and have an interest in maintaining the status quo (Ladrech, 2006; Day, 2005). Campaigns, even for European elections, are oriented in the national context (Hertner, 2013).

The case of Volt

Volt fits neatly in Niedermayer's (1983) third phase: a pan-European party where the national parties are branches of a pan-European party. Volt has a centralized leadership at the European level. The political work is coordinated at the EU level rather than nationally (Kolster and Homeyer, 2019). As Kolster and Homeyer (2019:10) describe, ‘[a]ll Volt national chapters [...] run with the same program’. It is not the first party to attempt this model, but previous parties were neither successful, nor sustainable (Leruth, 2021; Lefkofridi, 2020).

The party was founded in 2017 by Andrea Venzon, an Italian student; Colombe Cahen, a French lawyer; and Damien Boeselager, a German journalist (Kolster and Homeyer, 2019). They were upset by the decision of the UK to leave the EU (Kolster and Homeyer, 2019; Gieda, 2019). The group wanted to deepen and democratize the European project. They combined their ambition for a European federation with a social-liberal programme that aimed for global cooperation, human rights, sustainable development, the empowerment of citizens and digitalization of public services (Kolster and Homeyer, 2019): Volt sees itself as ‘pan-European, pragmatic and progressive’ (Klein, 2020: 9).

In the 2019 European parliament election, Volt participated in seven of the 28 European member states at the time (see Table 1). In Germany, Luxembourg and the Netherlands, the party won more than 0.5% of the vote. In Germany, the party won its only actual European Parliament seat. After an internal referendum, this Volt Member of the European Parliament joined the group of the Greens/European Free Alliance (Klein, 2020: 4). After that, Volt participated in eleven national elections, winning seats in the Netherlands and Bulgaria. These are two different situations: Volt Netherlands won 2.4% of the vote, enough for three seats in the extremely proportional Dutch electoral system (Otjes and Voerman, 2022). Volt Bulgaria participated as part of electoral coalitions (Spirova, 2022). Bulgaria saw three elections because of the inability of the political elites to form a governing coalition: in the 2021 April and July elections, Volt was part of the anti-corruption coalition ‘Stand up! Maffia, get out!’. In November, it was part of the anti-corruption coalition ‘We Continue the Change’. In the November elections, this coalition became the largest bloc in the Bulgarian parliament, and two of its 67 seats were allocated to Volt. In the 2022 elections, the bloc lost seats and votes but Volt retained its seats. In Italy, Volt was part of the alliance around the Democratic Party, but it did not win national representation.

Table 1.

Volt national-level election results 2019–2022.

Country	2019	2021	2022
Belgium	0.3%^E
Bulgaria	0.2%^E	4.7% (April/)^NC 5.0% (July)^NC 25.3% (Nov)^NCS	19.5%^NCS
France			<0.1%^N
Germany	0.7%^ES	0.4%^N
Italy			19.1%^NC
Luxembourg	2.1%^E
Malta			0.1%^N
Netherlands	1.9%^E	2.4%^NS
Portugal			0.1%^N
Spain	0.2%^E
Sweden	<0.1%^E		<0.1%^N

Note: E = European election; N = national election; C = as part of coalition; S = party obtained seats.

Even though Volt is a pan-European party in which the national branches are bound by the pan-European program, the leadership realized that national campaigns require adaptation to the national situation (Klein, 2020: 52): as the secretary-general of Volt Europe said (in an interview in Gieda, 2019: 45), ‘So in Germany we can communicate that we are progressive, but we cannot do that in Bulgaria or in Greece, or even in Portugal. Because in Greece progressive means left’. As Klein (2020: 52) shows, Volt chose to highlight specific elements of its manifesto in specific countries: more right-wing in post-communist countries, more left-wing in Western countries, more focused on moral and cultural issues in polities with many pro-European parties and more pro-European in more Eurosceptic systems.

This case study will focus on the voters of Volt in the 2021 Dutch national elections. One reason for this case study is pragmatic: the Dutch 2021 election survey has a sufficient number of Volt voters to make statements with some confidence about its supporters. In other national and European election surveys, there are too few Volt voters for statistical analysis.²

The second reason to study the Dutch case is that – although it is difficult to assess a priori whether Volt Netherlands is representative of Volt in other countries – it does provide an important context in which Volt has been far more successful than Volt branches in other European countries. The success of Volt Netherlands could be due to an electoral system that is far more open to new parties than most of Europe. This highly proportional electoral system results in a diverse and fragmented party landscape. After the 2021 elections, 17 parties are represented in parliament with five parties still smaller than Volts’ three seats in a 150-seat parliament. Thus, the Dutch case provides important insights into under what conditions voters support a new, pan-European party.

Volt Netherlands was founded on 23 June 2018. It was one of the first national branches of Volt. This branch got 1.9% of the vote in the 2019 European Parliament election, which was the second-best score in the EU, but only half of what was necessary for a European Parliament seat in the Dutch constituency. In the 2021 Dutch lower house election, the party got 2.4% of the vote and three out of 150 seats. Their national manifesto was generally similar to the programme of Volt Europe with one major difference: nuclear energy. Volt Netherlands sees nuclear energy as a necessary part of a sustainable energy mix in the short to medium term, including the construction of new nuclear power plants. Volt Europe opposed nuclear energy because of nuclear waste and the potential for catastrophic accidents. The Volt Europe manifesto proposed closing existing nuclear power plants. In 2020, Volt ‘refined’ its energy strategy, taking a less outspoken stance on nuclear energy (Klein, 2020: 29–61).³

After Volt Netherlands won seats in the Dutch parliament, its membership soared. This led to an imbalance in the membership of Volt Europe: by August 2021, the Dutch branch had more than 10,000 members, which was double of what the other branches had in total (see Online appendix). What started as a pan-European party is now in majority a Dutch political party. In the 2022 municipal election, Volt participated in 10 Dutch municipalities. In these municipalities, the party won on average 5% of the votes. Just before these elections, the lower house parliamentary party group came into conflict with Member of Parliament (MP) Nilüfer Gündoğan, who was expelled over what the party described as transgressive behaviour. Volt was also successful in the 2023 provincial elections, particularly in cities with large student populations, gaining 3.0% of the national vote and two seats in the indirectly elected 75-seat Senate.⁴

In order to consider the ideological and strategic niche of Volt, one can look at Figures 1A, 1B and 1C.They show six different lines of conflict, three of which are often used in the literature (Kriesi et al., 2006; Irwin and Van Holsteyn, 2008) and three of which are pertinent for understanding the case of Volt.⁵ Figure 1A shows the economic left-right dimension and the pro-/anti-EU dimension. The first dimension concerns the conflict over income redistribution and divides the left that favours a more equal distribution of income from the right that accepts income differences as a way to stimulate performance. The second concerns the conflict on the different visions of the EU, moving from hard Eurosceptics that reject their country's EU membership, via soft Eurosceptics who oppose the current direction of European integration, and those who favour further European integration, to those who favour a fully fledged European federation (Mudde, 2012; Toshkov and Krouwel, 2022). On these dimensions, there is no clear niche for Volt as it stands in the pro-European economic centre together with D66.

Figure 1.

Parties in the Dutch political space 2021. (A) Parties on the economic and the European Union (EU) integration dimension. (B) Parties on the moral and cultural dimension. (C) Parties on the environmental dimension and nuclear power item.

Figure 1B shows the moral and cultural dimensions: the moral dimension divides those who favour traditional, conservative morality and those who favour a progressive, liberal approach to moral issues. Among others, this relates to the place of women and queer people in society. Until the early 2000s, the economic and the moral dimension sufficed to understand the political landscape. Since the 2000s, the cultural dimension played a major role in Dutch politics. This divides those who favour immigration and a multicultural society and those who want to close the borders to immigration and want the Netherlands to have a dominant Dutch culture. Overall, this is further entwined with issues related to law and order, safety, civic integration and Islam. This now divides more patriotic voters and parties from those who have a more cosmopolitan, multiculturalist view. On both these issues, Volt has an extremely progressive position, which it shares with four other parties, also indicating that Volt has no clear niche on moral or cultural issues.

Figure 1C shows two dimensions related to environmentalism. These do not necessarily structure the Dutch political system but are of secondary importance in the European context (Huijsmans and Kouwel, 2021) and may matter for Volt specifically. The horizontal dimension concerns environmentalism in general terms. It divides parties who prioritize economic growth over measures to combat climate change and those who accept lower economic growth in order to combat climate change (Dunlap and Scarce, 1991; Johnson et al., 2005). The vertical dimension concerns the issue of nuclear energy, which Volt favours. Here, we can see a clear niche for Volt, since it is the only environmentalist party that is pro-nuclear, as it is pro-growth parties that support nuclear energy. That Volt's support for nuclear energy differentiated it from the other left-wing parties was highlighted prominently by the traditional print media. The party was also endorsed by progressive comedian Arjen Lubach in his show Zondag met Lubach (a popular carbon copy of the Tonight Show). Lubach shared the party's support for nuclear energy. Prominent journalist Rob Wijnberg also endorsed the party, highlighting its support for nuclear energy.⁶

Hypotheses

This discussion provides us with two hypotheses. Our first hypothesis reflects the motivation of its founders to deepen and democratize EU integration. We embedded this further in the notion that Volt as a pan-European party is the third phase of the development of Europe's parties which seeks to construct a truly transnational political space: in this case, Volt wins support because of its common pro-European program. Individuals will vote for Volt because it is a pro-European party that mobilizes voters by activating the pro-/anti-EU cleavage. Its pan-European nature shows the credibility of Volt as a pro-European project. Volt is a single-issue EU integration party (Leruth, 2021). In that case one would expect that:

H1 (EU integration hypothesis): The more voters support EU integration, the more likely it is that they vote for Volt.

Our second hypothesis reflects the literature on the importance of the political opportunity structure for new party success. In that case, the success of Volt reflects the specific niche that it cornered: that in this specific election there was a cluster of pro-environmental and pro-nuclear voters that no party catered to. This is not an EU-wide niche, and even if it were, it is not a niche that Volt would appeal to in other European states, because this is the issue where the Dutch Volt branch specifically differed from Volt Europe. It is a very specific political opportunity that this particular Volt branch mobilized on.

H2 (pro-nuclear environmentalist hypothesis): The more voters support both nuclear power and environmental protection, the more likely it is that they vote for Volt.

Data and methods

This study relies on two datasets: the 2021 Dutch Parliamentary Election Study (DPES) and the 2021 Kieskompas national election dataset. Both datasets have drawbacks: the DPES is a relatively small but rigorously representative sample. A small party like Volt is only supported by a limited number of voters (108 in this dataset). The Kieskompas data is based on respondents from a voting advice application (VAA) (Wall et al., 2014). This sample is not representative (which we address using weights), but it is very large: we have 5491 Volt voters. We do this to show the robustness of our results. This shows that the pattern that we find does not depend on a single dataset (the DPES or the VAA data).

The DPES is in itself a combination of two samples (Sipma et al., 2021; Jacobs et al., 2021): the Longitudinal Internet Studies for the Social Sciences (a panel drawn from the Central Bureau of Statistics population registry for the Netherlands) and a random sample of the entire population from the Dutch Personal Records Database. Both of these have around 2400 respondents.

The VAA data is composed of all respondents who used the VAA Kieskompas (Etienne et al., 2021). Before entering, the VAA respondents consent to their data being used for scientific research. At the end of the survey, they have the option of answering some additional questions for scientific purposes. A total of 1,607,487 individuals completely filled in this VAA, that is, 12% of the Dutch electorate. This huge sample, however, is not representative of the Dutch population due to its opt-in data collection. In order to provide nationally representative population estimates, we used weights. Two weighting methods were used for two different sets of variables. We used post-stratification for demographic characteristics and iterative proportional fitting for vote choice (Valliant, 1993; Rao et al., 2002). For the former, we used a joint demographic distribution of age (in four categories), gender (binary self-identification), educational attainment (in three categories), migration background and geographic region (province) based on population data from the Dutch Bureau of Statistics. Post-stratification involves partitioning sample respondents into demographic cells, that is, a particular combination of all the demographic characteristics. We know how many people sampled in the survey dataset are located in this cell. Given the available census data, we also know how much that differs from the actual population located in that particular cell. Via post-stratification, we use the difference between the number of respondents in the cell and the number of citizens in that cell in the population to compute frequency weights in each cell to ensure that the cell totals mirror the population totals within the used demographic categories.

In addition to taking demographic characteristics into account, the weighting also includes political preferences measured by vote recall in the 2021 parliamentary elections. Using raking, we made a second round of adjustments on top of the post-stratification. Official election results are available at the provincial level, and we use this to adjust for the partisan bias of the collected sample.⁷ We employ Iterative Proportional Fitting algorithms to make sure the national total vote recall in our data mirrors the actual election result, but also find an optimal solution to distribute the expressed vote recall across demographic cell levels. A total of 252,948 VAA respondents had answered enough background questions to allow for the calculation of weights. The weights that are higher than 99.5% of the highest weight were all fixed at the weight of this 99.5% highest weight.⁸

We look at three independent variables: in the DPES, we look at whether respondents voted for Volt. In VAA data, we look at whether respondents intend to vote for Volt and the propensity to vote for Volt. Again, we do this to show that the results we find are consistent between vote intention and the actual vote.

To measure the EU integration dimension, we make a scale in both datasets. In the DPES, we use a two-item scale about EU membership and EU integration. In the VAA data, we use a two-item scale about EU membership and EU economic integration. To measure the environmental dimension, we use a single item on climate change in the DPES and a three-item climate scale in the VAA data. Both datasets have one item regarding nuclear power. The specific items are listed in the Online appendix.

In this study, we control for seven factors. The first three are the cultural dimension, the moral dimension and the economic dimension, mentioned above. These structure voting behaviour in general. To measure the cultural dimension, we use a six-item scale in the DPES, which covers issues related to immigration, civic integration and safety. In the VAA data, we use an eight-item scale on similar issues. For the moral dimension, we use a two-item scale in the DPES (on same-sex adoption and euthanasia) and one single item in the VAA data (on abortion). To measure the economic dimension, we use a two-item scale in DPES, which concerns redistribution. We use a four-item scale in the VAA data which concerns taxes and poverty. Then, we control political dissatisfaction: we know that voters sometimes vote for new parties out of dissatisfaction with and distrust in the established parties (Bergh, 2004). Voting for a new party is sometimes a protest vote, as a signal of discontent with established parties (Kselman and Niou, 2011). New party success in the aggregate often correlates to other indicators of political dissatisfaction (Tavits, 2006). Volt has been described as explicitly anti-populist in journalistic accounts, making it unlikely that the party would appeal to the most dissatisfied voters (Erdbrink, 2021). In practice, controlling for political satisfaction is also complicated. The DPES has two sets of items, a five-item political cynicism scale and an item regarding whether respondents are satisfied with the government. Such items are missing from the VAA data. It does include an item on whether respondents regretted their vote in the previous election, which we use as a proxy for political dissatisfaction. Finally, we control for three commonly used demographic characteristics: gender (whether respondents identify as male), education (whether respondents have a degree from a research university or a university of applied sciences) and age (whether respondents are younger than 30). In the last two, the expectation is that Volt appeals most to younger and higher-educated voters. The descriptives are listed in the Online appendix.

In the Online appendix, we show three sets of additional analyses. The first examines the patterns presented in the article without any controls. The second shows the results for the VAA data with untrimmed weights. Finally, we analyze the difference between Volt and D66, its most important competitor.

Descriptive results

Before turning to the regressions, it may be useful to illustrate how Volt voters situate themselves in the political spaces presented above. We use data from the DPES to show this. Figure 2A shows where Volt voters stand on average on the European integration and economic left-right dimensions: Volt voters are the most pro-European voters (followed by GreenLeft voters, voters of the social-democratic PvdA and the social-liberal D66). On average, they have a center-left economic positioning (which they share with D66, among others). They are progressive on both moral and cultural issues and statistically indistinguishable from D66 and the Labour Party (Figure 2B). Finally, when it comes to environmentalism and nuclear energy (Figure 2C), Volt voters are on average pro-environmental (like D66) and pro-nuclear (like the conservative liberal VVD). On these two dimensions, the position of Volt's voters is most unique. There appears to be a striking consistency between the party placement of Volt in the party placement data in Figure 1A-C and the survey data, in particular when it comes to their pro-nuclear environmentalism. From this data, it may appear that ‘Volt has the best campaign team in the world, as if they conducted a study of voter attitudes to find a niche, and then placed themselves directly in that niche’.⁹

Figure 2.

Voters in the Dutch political space 2021. (A) Parties on the economic and the European Union (EU) integration dimension. (B) Parties on the moral and cultural dimension. (C) Parties on the environmental dimension and nuclear power item.

Of the voters in the DPES that are most pro-nuclear and most pro-environmental, 24% voted for D66, and 17% voted for Volt. Out of the voters that are most pro-European, 28% voted for D66, and only 10% for Volt. In this category, PvdA and VVD score between D66 and Volt. It is clear from this data that D66 is the key competitor of Volt. When it comes to its economic, environmental, European, cultural and moral positions, D66 is always very close. Therefore, in the Online appendix, we put the spotlight on the difference between D66 and Volt. Here, we find that demographic differences play a key role (with Volt doing better among young and male voters). Volt also attracts voters that are less satisfied with the government or their previous vote choice. When it comes to EU integration or nuclear power, the results are less consistent.

Regression results

This section presents 15 regressions, shown in Tables 2 to 4, with the same five regressions being replicated for vote choice in the DPES data, the vote intention in the VAA data and propensity to vote (PTV) from the VAA data. For each, we look at one model with the European dimension, one with attitudes towards the environment and nuclear power, one with an interaction between those two, a model with attitudes towards the EU, environmentalism and nuclear energy and a final model with the interaction between environmentalism and nuclear energy and attitudes towards the EU. The visualizations of these final models are included in Figures 3 to 5. All models include controls for attitudes towards the economy, cultural issues and morality as well as respondents’ age, education level, gender and political satisfaction.

Figure 3.

Environmentalism, support for nuclear power and voting for Volt.

Figure 4.

Environmentalism, support for nuclear power and intending to vote for Volt.

Table 2.

Logistic regression results of vote choice on DPES data.

Model	Model 1	Model 2	Model 3	Model 4	Model 5
Intercept	−8.60***	−10.04***	−6.84***	−10.77***	−7.67***
	(1.36)	(1.42)	(1.61)	(1.47)	(1.65)
European dimension	2.74***			2.12**	2.05**
	(0.70)			(0.71)	(0.71)
Environmental item		3.55***	−0.39	3.12***	−0.67
		(0.74)	(1.30)	(0.76)	(1.31)
Nuclear item		1.54**	−3.53*	1.58**	−3.37*
		(0.48)	(1.63)	(0.48)	(1.65)
Environmental item * Nuclear item			6.08**		5.93**
Environmental item * Nuclear item			(1.93)		(1.94)
Economic dimension	1.40	1.81*	1.95*	2.12*	2.24*
	(0.81)	(0.85)	(0.86)	(0.88)	(0.88)
Cultural dimension	1.44	1.97*	2.15*	1.16	1.36
	(0.98)	(0.98)	(0.99)	(1.02)	(1.03)
Moral dimension	0.60	0.45	0.38	0.17	0.14
	(0.86)	(0.82)	(0.82)	(0.85)	(0.85)
Political cynicism	0.38	−0.43	−0.59	0.25	0.09
	(1.06)	(1.05)	(1.08)	(1.07)	(1.11)
Government dissatisfaction	1.30	1.12	1.22	1.29	1.39
Government dissatisfaction	(0.68)	(0.69)	(0.70)	(0.70)	(0.71)
Education = higher	0.18	0.08	0.11	0.05	0.08
	(0.29)	(0.30)	(0.30)	(0.30)	(0.30)
Gender = male	0.78*	0.68*	0.68*	0.52	0.52
	(0.31)	(0.32)	(0.32)	(0.32)	(0.32)
Age < 30	1.71***	1.41***	1.40***	1.42***	1.40***
	(0.29)	(0.30)	(0.30)	(0.30)	(0.31)
N	1597	1597	1597	1597	1597
AIC	460	443	436	436	429

Note: ***p < 0.001; **p < 0.01; *p < 0.05.

Table 3.

Logistic regression results of vote intention on the VAA data.

Model	Model 6	Model 7	Model 8	Model 9	Model 10
Intercept	−8.95***	−10.66***	−9.19***	−11.39***	−9.85***
	(0.13)	(0.15)	(0.27)	(0.16)	(0.28)
European dimension	3.33***			2.68***	2.70***
	(0.14)			(0.14)	(0.14)
Environmental item		3.38***	1.62***	2.96***	1.10***
		(0.14)	(0.31)	(0.15)	(0.31)
Nuclear item		2.42***	0.32	2.34***	0.12
		(0.07)	(0.34)	(0.07)	(0.35)
Environmental item * Nuclear item			2.50***		2.65***
Environmental item * Nuclear item			(0.40)		(0.41)
Economic dimension	1.30***	1.07***	1.05***	1.17***	1.16***
	(0.11)	(0.12)	(0.12)	(0.12)	(0.12)
Cultural dimension	2.55***	3.33***	3.34***	2.21***	2.22***
	(0.13)	(0.13)	(0.13)	(0.14)	(0.14)
Moral dimension	1.00***	0.79***	0.81***	0.77***	0.79***
	(0.08)	(0.08)	(0.08)	(0.08)	(0.08)
Vote dissatisfaction	0.55***	0.41***	0.41***	0.51***	0.51***
	(0.08)	(0.08)	(0.08)	(0.08)	(0.08)
Education = higher	0.18***	0.15***	0.16***	0.08	0.09*
	(0.04)	(0.04)	(0.04)	(0.04)	(0.04)
Gender = male	0.53***	0.41***	0.43***	0.30***	0.31***
	(0.04)	(0.04)	(0.04)	(0.04)	(0.04)
Age < 30	0.50***	0.16**	0.15**	0.19***	0.18***
	(0.05)	(0.05)	(0.05)	(0.05)	(0.05)
N	117,588	117,588	117,588	117,588	117,588
AIC	25,670	24,580	24,548	24,184	24,149

Note: ***p < 0.001; **p < 0.01; *p < 0.05; trimmed weights.

Table 4.

Linear regression results of PTV on the VAA data.

Model	Model 11	Model 12	Model 13	Model 14	Model 15
Intercept	−0.68***	−1.83***	−1.49***	−1.93***	−1.61***
	(0.05)	(0.06)	(0.08)	(0.06)	(0.08)
European dimension	2.00***			1.48***	1.47***
	(0.06)			(0.07)	(0.07)
Environmental dimension		2.17***	1.65***	1.82***	1.34***
Environmental dimension		(0.06)	(0.10)	(0.06)	(0.10)
Nuclear item		1.38***	0.81***	1.31***	0.78***
		(0.04)	(0.09)	(0.04)	(0.09)
Environmental dimension * Nuclear item			0.91***		0.84***
Environmental dimension * Nuclear item			(0.14)		(0.14)
Economic dimension	0.59***	0.64***	0.62***	0.56***	0.54***
	(0.06)	(0.06)	(0.06)	(0.06)	(0.06)
Cultural dimension	2.92***	3.44***	3.46***	2.58***	2.61***
	(0.07)	(0.07)	(0.07)	(0.08)	(0.08)
Moral item	1.11***	1.05***	1.06***	1.04***	1.05***
	(0.04)	(0.04)	(0.04)	(0.04)	(0.04)
Vote dissatisfaction	0.15***	0.09*	0.09*	0.13**	0.13**
	(0.04)	(0.04)	(0.04)	(0.04)	(0.04)
Education = higher	0.57***	0.53***	0.54***	0.49***	0.50***
	(0.02)	(0.02)	(0.02)	(0.02)	(0.02)
Gender = male	0.66***	0.61***	0.62***	0.55***	0.56***
	(0.02)	(0.02)	(0.02)	(0.02)	(0.02)
Age < 30	0.75***	0.62***	0.61***	0.66***	0.65***
	(0.04)	(0.04)	(0.04)	(0.04)	(0.04)
N	71,967	71,967	71,967	71,967	71,967
R-squared	0.17	0.18	0.18	0.19	0.19
AIC	381,464	380,313	380,270	379,796	379,760

Note: *p > 0.1 > ** p > 0.05 > *** p > 0.01; trimmed weights.

The three models that focus on EU integration only indicate that (as expected) voters who favour EU integration are more likely to vote for Volt. When moving from the most Eurosceptic to the least Eurosceptic voter, the likelihood of voting Volt increases about 20-fold. In the DPES, it increases from 0.3% to 3.8%, and in the VAA data, it increases from 0.1% to 3.8%. The propensity of voting for Volt is two points higher (on an 11-point scale), showing that in line with the EU integration hypothesis, Volt attracts pro-European voters.

The three models that focus on attitudes towards the environment and nuclear power separately indicate that both factors strongly predict voting for Volt. The most environmentalist voter is about 30 times more likely to vote for Volt than the least environmentalist voter. The vote propensity for Volt increases by two points on an 11-point scale. Nuclear power has a smaller effect: the most pro-nuclear voter is between three and 10 times more likely to vote for Volt than the most anti-nuclear voter. The PTV increase is more than one point. When we compare the model fits between Models 1, 6 and 11, on the one hand, and 2, 7, and 12, on the other, we see an interesting pattern: the models with only nuclear power and environmentalism score markedly lower than the models with only EU integration (17 points for Models 1 and 2, about 1000 points for Models 6, 7, 11 and 12). This indicates that the items related to the environmental niche are a much better fit for the data than the EU items (Burnham and Anderson, 2004: 271). The coefficient of determination (R-squared) in Table 4 shows the same pattern. Model 3 adds an interaction between the two environmental items, allowing us to see whether Volt performs particularly well in its niche of pro-climate but pro-nuclear voters. The interaction terms indicate that this is the case. The Akaike Information Criterion (AIC) values for Models 7, 8, 12 and 13 also indicate that the environmental/nuclear interaction is a better fit for that data than the model without interactions.¹⁰ These results are in line with the pro-nuclear environmentalist hypothesis.

The next models combine EU, environmental and nuclear attitudes. Compared to the previous models, here the effect of EU models in particular has decreased. Still, all three models are significant predictors of voting for Volt. The AICs for Models 8, 9, 13 and 14 indicate that including the EU integration item leads to a significantly higher fit than if it were not included; this is not the case when using the DPES data. In these models, we can directly compare the effect size of environmentalism, EU integration and support for nuclear energy. A one standard deviation increase in support for EU integration increases the chance to vote for Volt by 89% in the DPES (by 85% in the VAA data). This increase raises the PTV for Volt by 0.3 (on a scale from 0 to 10). A standard deviation rise in a respondents’ environmentalism increases the chance to vote for Volt by 150% in the DPES (by 103% in the VAA data). This increase boosts the PTV for Volt by 0.4 (on the same 0 to 10 scale). A one standard deviation increase in support for nuclear energy increases the chance to vote for Volt by 70% (by 107% in the VAA data). This increase augments the PTV for Volt by 0.4. Consistently when it comes to effect sizes, the EU dimension matters less for voting for Volt than the environmental dimension.

In the final models, we add the interaction between environmentalism and nuclear attitudes. These all show significant effects. These are visualized in Figures 3 to 5. Figure 3, which comes from the markedly smaller DPES dataset, shows the highest level of uncertainty. This shows that when voters do not support nuclear power, the chance to support Volt is low, whether or not they want to make sacrifices to fight climate change. As respondents become more pro-nuclear, the difference between the pro- and anti-climate action respondents becomes larger: nearly 10% of the most pro-nuclear and pro-environment voters vote for Volt. In the DPES model, a one standard deviation increase in pro-EU nearly doubles the chance to vote for Volt. The interaction requires more explanation. For voters who are not at all environmentalist, a one standard deviation increase in support for nuclear power decreases the chance to support Volt by two-thirds. Among those who are most environmentalist, a one standard deviation increase in support for nuclear power increases the chance to vote for Volt by 20%. Combined, this means that the gap in the chance to vote for Volt between those who are most and least environmentalist becomes four times greater due to this one step on nuclear power.

Figure 5.

Environmentalism, support for nuclear power and propensity to vote for Volt.

Figure 4 shows the same pattern but with much smaller levels of uncertainty: voters opposed to climate action never vote for Volt, but if we look at voters who favour climate action, the difference between those who oppose nuclear energy (of whom 0.6% vote for Volt) and those who favour nuclear energy (of whom 8.5% vote for Volt) is striking. If we look at a one standard deviation increase in support for nuclear energy, this increases the chance to vote for Volt by only 4% among those who are least environmentalist. Among those who are more most environmentalist, the increase in support for Volt is sevenfold. In the same model, a one standard deviation increase in support for European integration doubles the chance of voting Volt.

Figure 5 shows the same pattern for the PTV. It shows that there is a small increase in the propensity to vote for Volt among those who oppose climate action as they become more pro-nuclear: a one standard deviation increase in support for nuclear energy raises the PTV for Volt by 0.2 (on a scale from zero to ten). Among those who favour climate action, a one standard deviation increase in support for nuclear energy boosts the PTV for Volt by 0.4 points. In the same model, a one standard deviation increase in support for EU integration augments the PTV for Volt by 0.3.

When we look at our control variables, we see a number of consistent patterns: Volt does better among voters with right-wing economic views than among voters with left-wing economic views. All analyses show that voters younger than 30 make up the core of Volt supporters. The other effects are less consistent: Volt does better among voters with more cosmopolitan views on the cultural dimension (although this effect is no longer significant in the DPES data once EU integration is included). In the VAA data, Volt also does better among morally progressive voters. There is no consistent effect of political dissatisfaction, the DPES indicates a weakly and not always consistently significant effect of dissatisfaction with the government; the VAA data shows that those who intend to vote for Volt tend to regret their previous vote, but for the PTV, this significance of the coefficient is not consistent. The relationships of Volt support with education level and gender show less consistently significant effects. There is no education effect in the DPES, and it is only consistently significant for PTV in the VAA data. Men tend to support Volt more than others, but this is not consistently significant in the DPES.

In the Online appendix, we look at the results without control variables and with untrimmed weights. These analyses support the results presented here substantially.

Discussion and conclusion

This article studied the supporters of a small party in a small European state. What is the relevance of these results outside of the case of the Netherlands? Volt is not just a small party in a small European country. It is a party with big ambitions: to be the first truly pan-European party in Europe, that is, the next stage in the evolution of party politics in the EU and an important driver of a deeper and more democratized EU. This article sought to assess what happens to these ideals in the reality of electoral competition.

Indeed, we find that the more pro-European respondents are, the more likely they are to favour Volt. In each of the three empirical studies, we see that the pan-European party appeals to a pro-European electorate. We find ample support for the EU integration hypothesis. However, when we compare this to the pro-nuclear environmentalist hypothesis, we find that this second hypothesis offers a stronger explanation of why people vote for Volt. The party appeals to voters that favour both climate action and nuclear energy. Just below 10% of the voters who favour this kind of nuclear environmentalism support Volt, compared to only just below 4% of those who are most pro-European. Volt Netherlands appealed to a very specific niche and did so successfully. This is clear support for our pro-nuclear environmentalist hypothesis.

What does that say about the pan-European project of Volt? Nuclear power was not one of the core planks of Volt. Rather, it is an issue that divides the different national chapters of Volt Europe. By giving the Dutch branch the autonomy to pursue its own energy policy, the party won national representatives. But this does show the difficulty of campaigning as a pan-European party in different national political contexts. The specific political opportunity structure in every country determines the success of a new party. Rather than a truly ‘European’ party, Volt Netherlands behaved very much as a traditional ‘Downsian’ party: it found an ideological niche that was not currently occupied and moved to get support. It appears to be the case that Volt Netherlands is not fundamentally different from other new parties: it was able to gain support in an institutionally open environment, subsequently tailoring its programmatic appeal to a specific electoral niche.

One may wonder whether this ‘Downsian’ strategy is viable elsewhere in Europe. The openness of the Dutch electoral system allowed Volt to win three seats in parliament with only 2% of the vote. Given that most European countries have an (effective) electoral threshold that is much higher than the 0.67% in the Netherlands, parliamentary representation is not as easily attainable elsewhere. Moreover, the best strategy differs from system to system. The importance of programmatic niches vis-á-vis mobilization strategies based on anti-establishment sentiment may differ, for instance, between Western, Central and Eastern Europe (Kseslman et al., 2016). In this sense, it is notable that Volt campaigned on the basis of a specific programmatic appeal in the Netherlands and as part of an anti-corruption alliance that voices popular discontent with the sitting government in Bulgaria.

The leeway that Volt Europe gives to the national branches to pursue these specific opportunity structures shows the political savvy of its leadership. It does, however, cast doubts on the pan-European ambitions of Volt. If the European manifesto of Volt has to be written in such a way that it allows every national Volt branch to appeal to their own base, how does this manifesto differ from the lowest common denominator manifestos of the existing parties at the European level (Kolster and Homeyer, 2019; Ladrech, 2006)? One may question how Volt is well-served by having MPs in a national parliament that are elected on a national platform with prominent elements that sit uneasily with Volt's European platform. One may even question how European democracy is well-served by having Dutch Volt representatives defending in a national parliament an agenda favourable to nuclear energy production when we know that the European public at large does not favour this (Kovacs and Gordelier, 2009).¹¹ In the multilevel democracy of the EU with its mix of Europarties and national parties, representation is already complex (Lefkofridi and Katsanidou, 2014; Thorlakson, 2017). Volt sought to overcome these issues, but the same tension between European ideology and national opportunities rears its head.

It is highly unlikely that these specific results are representative of Volt in other European countries. We argue that the lack of generalizability is an important outcome for our study, not a weakness: this negative outcome shows that the specific national political opportunity structure mattered greatly for the party's success. That fact that this issue was the major point where Volt Netherlands deviated from the branches elsewhere reinforces this point: even if there were pro-nuclear, pro-climate niches there, the other anti-nuclear Volt branches are unlikely to appeal to those. The Dutch Volt branch competed successfully on a policy position which is not shared by the party's European leadership. That is, one cannot generalize from these results. This in itself contradicts the party's self-image as a pan-European party with national branches. This is not just the case for Volt Netherlands: as Klein (2020) shows, Volt adapts its political message to specific national electoral niches. Therefore, the issue is not just that we cannot generalize from these results. In the end, these results cast doubts on what being a pan-European party actually is and whether it is substantively different from other Europarties.

This article speaks to different literatures. Regarding the literature on new party success, it shows three things. Firstly, it reinforces the importance of political opportunity structures. These are not just niches in terms of a specific area on the left-right dimension being unattended but can also be a very specific set of issue positions. New parties can appeal to specific niches, in particular in open electoral systems like the Netherlands. Secondly, what is striking about Volt is the relative lack of political dissatisfaction among its voters. We know that political dissatisfaction predicts why people vote for new parties more generally, but Volt did not mobilize voters who strongly distrust politicians. Rather, there is some indication that they regretted their last vote but that they were mainly motivated by a specific programmatic offer that Volt Netherlands made. Thirdly, Volt Netherlands is an example of the branching model of new party formation, where a transnational party starts new national parties as chapters. We show that the appeal of the most successful national branch of Volt does not square with this pan-European ambition, as it appealed to a specific niche in this country with a specific plank that is absent from the pan-European program. This is one indication that it is difficult for a new party to tell the same story in every country.

The results are less hopeful for the literature on the evolution of political parties at the European level. Volt was an attempt at a pan-European political party, where the European programme is leading and the European executive committee directs action. Such a pan-European party is seen as a necessary step for a truly pan-European democracy by prominent democratic theorists (Niedermayer, 1983; Andeweg, 1995; Habermas, 2015). While Volt has this pan-European organization, it does not appeal to voters in a pan-European way. It found a specific niche in a specific country that allowed it to win seats. The differentiation to national contexts that Volt allows for electoral strategic reasons undermines its pan-European ambition. In many ways, it operates in the same way as the Europarties that it seeks to replace: it runs in specific elections with a manifesto that is vague enough to allow a great diversity of national parties to adapt to specific national contexts (Klein, 2020).

Future research may want to pursue this issue further. While analyzing the vote choice for Volt of individual citizens might indeed be practically difficult outside of the Netherlands, it may be possible to see to what extent the (lack of) electoral success of Volt branches elsewhere may be due to the programmatic profile of these branches.

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Footnotes

Acknowledgements

The authors want to thank the editor and the three anonymous reviewers for their useful comments and suggestions and Niki Haringsma for his excellent editorial assistance.

Author contributions

Simon Otjes drafted the introduction, theory sections, case description, hypotheses, data and methods, descriptive and regression results and discussion and conclusion section and executed the statistical analyses. André Krouwel spearheaded the VAA data collection, critically revised the article and proposed the tile. Both agreed to be accountable for all aspects of work ensuring integrity and accuracy.

Funding

The author received no financial support for the research, authorship and/or publication of this article.

ORCID iDs

Simon Otjes

André Krouwel

Supplemental material

Supplemental material for this article is available online.

Notes

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