Religion has long been considered an important determinant of voting behaviour. However, the secularisation of Western societies has changed its role. Secularisation not only limits the political relevance of religion, it may also affect the nature of religious cleavages themselves. While extant literature suggests that differences between religious denominations are in decline, with regard to differences between religious and non-religious voters there are two divergent expectations, (1) that these differences are also in decline and (2) that there is an increased polarisation between the religious and the non-religious. For the latter expectation, evidence has already been found regarding the United States. In this paper, we examine whether a similar change can be observed in Western Europe. Combining data from the European Social Survey (ESS) and information on parties’ positions from the Chapel Hill Expert Survey (CHES), we assess the nature of over-time changes in the connection between religion and the vote choice. The results point to an increased polarisation between members of a Christian church and the non-religious, however, we also find that non-Christians are more similar to the non-religious than to Christians. We also uncover a growing division between Catholics and Protestants that does not fit common expectations. These findings challenge earlier work on the political consequences of secularisation and lead to new research questions.

Parties have an incentive to take up extreme positions in order to achieve policy differentiation and issue ownership, and it would make sense for a party to stress these positions as well. These incentives are not the same for all issues and all parties but may be modified by other strategic conditions: party size, party system size, positional distinctiveness and systemic salience. Using manifesto‐based measures of salience and expert assessments of party positions, the findings in this article are that parties emphasise extreme positions if, first, they are relatively small in terms of vote share; second, the extreme position is distinctive from those of other parties; and third, other parties fail to emphasise the issue. These findings have consequences for our understanding of party strategies, party competition and the radicalisation of political debates.

Which parties use simple language in their campaign messages, and do simple campaign messages resonate with voters’ information about parties? This study introduces a novel link between the language applied during election campaigns and citizens’ ability to position parties in the ideological space. To this end, how complexity of campaign messages varies across parties as well as how it affects voters’ knowledge about party positions is investigated. Theoretically, it is suggested that populist parties are more likely to simplify their campaign messages to demarcate themselves from mainstream competitors. In turn, voters should perceive and process simpler campaign messages better and, therefore, have more knowledge about the position of parties that communicate simpler campaign messages. The article presents and validates a measure of complexity and uses it to assess the language of manifestos in Austria and Germany in the period 1945–2013. It shows that political parties, in general, use barely comprehensible language to communicate their policy positions. However, differences between parties exist and support is found for the conjecture about populist parties as they employ significantly less complex language in their manifestos. Second, evidence is found that individuals are better able to place parties in the ideological space if parties use less complex campaign messages. The findings lead to greater understanding of mass‐elite linkages during election campaigns and have important consequences for the future analysis of manifesto data.

Switches produce a lack of credibility and damage a party's image, signalling weakness and an inability to select loyal MPs and preserve unity. Accordingly, we consider party out‐switching as a valence loss for the party. By combining information on party manifestos with a novel database on 2053 episodes of party switching, we investigate which electoral strategies parties adopt to reduce the negative consequences of such valence loss. Analyzing 1,131 manifestos related to 135 parties in 14 Western European democracies, from 1945 to 2015, we show that parties try to restore their positive image by investing on valence, in terms of competence, clarity and core issues. An instrumental variable approach corroborates our results. The findings have implications for spatial modelling, valence politics, issue ownership and issue competition.

Political parties and interest groups play a vital role in incorporating societal interests into democratic decision‐making. Therefore, explaining the nature and variation in the relationship between them will advance our understanding of democratic governance. Existing research has primarily drawn attention to how exchange of resources shapes these relationships largely neglecting the role of contextual conditions. Our contribution is to examine whether parties’ structured interactions with different categories of interest groups vary systematically with the pattern of party competition at the level of policy dimensions. First, we argue that higher party fragmentation in a policy space makes organisational ties to interest groups more likely, due to fears of voter loss and splinter groups. Second, we expect higher polarisation between parties on a policy dimension to make ties to relevant groups less likely due to increased electoral costs. We find support for both expectations when analysing new data on 116 party units in 13 mature democracies along nine different policy dimensions. Our findings underline the value of considering the strategic context in which parties and interest groups interact to understand their relationship. The study sheds new light on parties and interest groups as intermediaries in democracy and contributes to a new research agenda connecting interest group research with studies of parties’ policy positions and responsiveness.

The classical outbidding model of ethnic politics argues that democratic competition involving ethnic parties inevitably leads to ethnic outbidding where parties adopt ever more extreme positions. However, recent small‐N studies show that ethnic outbidding is only one of a range of strategies available to ethnic parties. This article seeks to explain why some ethnic parties are extremist, whereas others adopt moderate positions. Drawing on the ethnic outbidding and the nested competition model of ethnic party competition, it is hypothesised that the ethnic segmentation of the electoral market, and the relative salience of an ethnically cross‐cutting economic dimension of party competition, account for the varying degrees of extremism. Hypotheses are tested drawing on a novel, expert‐survey‐based dataset that provides indicators for the positions of 83 ethnonational minority parties in 22 European democracies in 2011. Results of ordinary least squares and two‐level linear regressions show that as the economic dimension gains importance, parties become more moderate relative to the party system mean. The electorate's ethnic segmentation has a positive effect on extremism, but this effect is not significant in all models. Contrary to expectations, higher ethnic segmentation of the party system is associated with more moderate positions in the majority of the estimated models.

Political parties face inherent risks when making election promises, as voters tend to penalize them for unfulfilled commitments. Nonetheless, parties make hundreds of promises. Why do parties engage in such precarious behaviour? I argue that parties employ a policy‐committing strategy when they need to increase the credibility of their policy programme and that they do so more today than previously because the political landscape has changed considerably in many Western democracies (time trend). Moreover, I expect parties to use the policy‐committing strategy more when they operate in a political arena with more competitors (system‐level factor), when they are a mainstream party (party‐level factor) and when they have increased the saliency of an issue (issue‐level factor). I test these four expectations with a unique, new dataset containing 330,850 quasi‐sentences coded from party manifestoes in 11 countries covering several decades of elections. Empirically, I find support for a time trend and show strong effects for the party‐level and issue‐level factors. However, a more competitive environment at the system level makes parties less, not more, likely to use the policy‐committing strategy. These results have important implications for party strategies, issue competition and policymaking in today's democracies.

Party competition sometimes resembles an auction, where parties seek to ‘buy’ elections through promises of economic largesse. In this article, I argue that whether parties engage in this practice will depend on political circumstances, such as the level of ideological competition. Incentives to promise more to voters will also vary depending on a party's electoral prospects: for parties that expect a significant level of government responsibility, promising too much is a risky strategy. I test these arguments by focusing on the spending commitments in party manifestos from 20 countries over the period 1945–2017. In line with expectations, parties tend to make more expansionary election pledges when ideological competition is more muted. In addition, left‐wing parties’ spending commitments are found to be influenced by their projected seat shares (based on opinion polls from before the start of the election campaign) relative to their competitors. Specifically, the stronger a left‐wing party's electoral prospects, the more fiscally conservative it tends to be, and vice versa.

Over the past two decades, extreme parties have gained increasing electoral success in European party systems. While this party polarization is often associated with its negative consequences, recent studies have suggested its potential benefit for remobilizing the electorate by offering clear political alternatives. However, it remains unclear which groups of citizens may be mobilized by broader supply and whether this positive effect is generalizable to multiparty systems. This article contributes to this debate arguing that the system multidimensionality matters when assessing the relationship between polarization and voter turnout. Through a multilevel analysis and two studies at the aggregate and individual levels, this article provides evidence that party polarization is associated with increased turnout only when parties polarize on the cultural dimension of party competition. This effect is moderated by the party system unidimensionality and mobilizes voters at large, regardless of their level of extremism, political awareness or partisanship. These findings support previous research suggesting a ‘realignment’ of party systems, meaning that the main line of political conflict for parties and voters is shifting towards the cultural dimension of party competition across Europe.

A large and growing body of research draws attention to the rising salience of socio‐cultural and identitarian issues and, potentially, the emergence of a new political cleavage that divides voters on those issues. However, the micro‐foundations of this transformation are less well understood. Here we take a voter‐perspective to evaluate how party competition has been restructured in the eyes of the voter. We leverage measures of citizens’ self‐reported probabilities to vote for alternative political parties in the European Election Study voter surveys between 1999 and 2019 in order to map electoral affinity and opposition among party families. We estimate to what extent spatial location on the economic left–right dimension and the GAL‐TAN dimension explain the patterns that emerge, and how this has changed over time. Our results provide evidence of a substantial shift in voter assessment from party competition structured along the economic left–right dimension to competition structured along the GAL‐TAN dimension. We also find great separation of TAN parties from other parties, with the deepest antipathy between the TAN parties and greens.

Having long shied away from proactively politicizing issues of European integration, the past crisis decade has put generally pro‐European mainstream parties under pressure to spell out more clearly which kind of Europe they support. We distinguish two such fundamental ideas of Europe: the redistributive polity, organizing transnational solidarity and the regulatory polity, strengthening national self‐reliance. Both notions are integrationist, but they come with distinct policy implications. What determines mainstream party support for either of these polity ideas? We investigate this question on data provided by the ‘EUandI’ voting advice application, which contains party positions on core issues of integration for all EU member states for the four European Parliament elections between 2009 and 2024. Mainstream party support for redistribution, we find, is generally driven by their ideological placement on the economic and cultural dimension. While progressive and left parties tend towards EU‐level redistribution, conservative and right parties are wedded to the idea of a regulatory European polity. This general dynamic, however, interacts with parties’ domestic considerations, that is, the public salience of an issue and a country's net‐payer status in the EU. We further find that the effect of mainstream parties’ ideological positioning differs across policy domains. While cultural and economic positions drive support for redistribution in fiscal and taxation policy to a nearly equal extent, support for redistribution in migration policy is driven by cultural factors alone, while in matters of security and defence right mainstream parties are more supportive of European solidarity than parties of the mainstream left. Our analysis demonstrates that mainstream parties now compete visibly over EU‐level redistribution, but that their stances on transnational solidarity differ depending on the domestic situation and the policy domain in question.

Political parties often adjust their policy agendas in response to changing electoral landscapes, balancing the need to appeal to new voters against the importance of retaining loyal supporters. While these patterns are generally well‐documented in the literature, the specific impact of voter availability on the electoral market remains underexamined. This article investigates how electoral opportunities – i.e., potential to mobilize new voters – and loyalty – i.e., likelihood of retaining current supporters – influence parties' decisions to expand or narrow their policy focus. To analyze this, the study integrates three decades of population data from the Comparative Study of Electoral Systems and European Election Studies with data on parties' issue focus obtained from the Manifesto Project. The analysis shows that parties strategically balance their focus between core and peripheral issues based on the anticipated utility of each approach. This strategy, however, depends on the stability of voter loyalty: expansion into new issues occurs primarily when voter loyalty is robust, although strong opportunities alone can also encourage agenda broadening. These findings contribute to understanding the calculated risks parties take in adjusting their issue attention and highlight why policy adjustments often backfire; namely, when misaligned with voters' availability on the market. This study speaks to the literature on party competition and representation in Europe, illuminating how electoral dynamics shape parties' policy focus.

How does public opinion affect political discourse on issues that parties struggle to deal with? Although scholars tend to analyse party–voter linkages in terms of policy positions, parties can respond to public opinion by changing both the positions and the salience of their policy agenda. Based on original time‐series data of party discourse and voter preferences in France, Italy and the United Kingdom (1992–2016), this paper analyses how mainstream parties have changed their political discourse on European integration in response to an increasingly Eurosceptic public. Results show that mainstream parties have adapted their positions to changes in public opinion and have at the same time deemphasized European Union issues in their discourse as the public grew Eurosceptic. Parties did not talk more about Europe even when they followed the tides of public opinion. These findings challenge our current understanding of party responsiveness, have implications for theories of party competition, and contribute to debates on the legitimacy of the European project.

The usefulness of the general class of spatial econometric models, which relaxes the assumption that the observations are independent, has only recently been realised. One particularly fruitful application includes models of parties' ideological change as well as the electoral consequences of party competition. In these studies, scholars can explicitly model the spatial interconnectedness of political parties in theoretically pleasing ways, producing inferences that are consistent with formal models of party competition, but are beyond the grasp of traditional ordinary least squares (OLS) regression models. To illustrate these benefits, this article replicates Adams and Somer‐Topcu's 2009 study of parties' responses to ideological shifts by rival parties to show that appropriately modeling patterns of interconnectivity between parties via weights matrices provides more realistic inferences that are more consistent with formal models of party competition.

Saliency theory is among the most influential accounts of party competition, not least in providing the theoretical framework for the Comparative Manifesto Project – one of the most widely used data collections in comparative politics. Despite its prominence, not all empirical implications of the saliency theory of party competition have yet been systematically tested. This article addresses five predictions of saliency theory, the central claim of which is that parties compete by selective issue emphasis rather than by direct confrontation. Since a fair test of the theory's assumptions needs to rely on data that measures party issue saliency and party positions independently, this article draws on new manifesto data from the Austrian National Election Study (AUTNES). Analysing all manifestos issued for the 2002, 2006 and 2008 general elections, it shows that saliency theory correctly identifies some features of party competition. For instance, parties disproportionally emphasise issues they ‘own’. Yet, the core assumption of saliency theory that parties compete via selective issue emphasis rather than direct confrontation over the same issues fails to materialise in the majority of cases.

Tensions between regionalist claimants and state‐wide governments remain the primary source of violent conflicts. Existing theories cannot systematically explain why and when state‐wide governments accede to such claims. Building on the partisan approaches developed so far, a theory of ideological authority insulation is constructed in this article. It is argued that the willingness of state‐wide parties to transfer authority to specific territorial entities is predominantly informed by ideological proximity to those entities. In a nutshell, the dominant conflict dimension in a country superimposes partisan rationales on the territorial dimension. A new dataset has been compiled with roughly 4,300 region‐cabinet dyads between 1945 and 2015, including electoral data, party positions and regional ‘centres of gravity’. Using panel rare‐events regressions, it is found that ideological proximity systematically explains the accommodation of minority demand controlling for alternative explanations from the partisan and ethnic conflict literature. The empirical evidence therefore supports adding ideological insulation and superimposition to the toolbox of partisan and conflict researchers. Additionally, the findings encourage the application of arguments from the conflict literature in established democracies and the testing of insights from partisan researchers in less democratic environments.

The appeal of far-right parties’ ideologies is one of the key drivers of such parties’ electoral wins in Europe. Most studies, however, have focused on the far right’s anti-immigrant or anti-minority discourse as the defining feature of this party family. In this article, we examine: (1) The conditions under which far-right parties benefit electorally from their Eurosceptic discourses, and (2) How center-right parties’ responses to the far right affect the latter’s electoral outcomes. The results of multilevel regression models show that when the distance between far-right and center-right parties’ positions toward European integration narrows, the vote share of far-right parties increases—but only up to a point. When the distance continues to narrow, without reaching zero, the far right’s vote share decreases. Our empirical analysis relies on the Chapel Hill Expert Survey series dataset and examines 75 cases of far-right parties in 22 European countries between 1999 and 2014. The findings suggest that center-right parties face a difficult strategic dilemma as they compete for votes with the far right: moving incrementally closer to the far right’s position can benefit the far right by intensifying competition over the issue of European integration. An almost full cooperation of the far right’s agenda, however, dampens the success of the far right. The center right must strike a balance that allows it to be responsive to Eurosceptic voters while retaining a centrist identity.

This study addresses the dynamics of the issue space in multiparty systems by examining to what extent, and under what conditions, parties respond to the issue ownership of other parties on the green issue. To understand why some issues become part and parcel of the political agenda in multiparty systems, it is crucial not only to examine the strategies of issue entrepreneurs, but also the responses of other parties. It is argued that the extent to which other parties respond to, rather than ignore, the issue mobilisation of green parties depends on two factors: how much of an electoral threat the green party poses to a specific party; and the extent to which the political and economic context makes the green issue a potential vote winner. To analyse the evolution of the green issue, a time‐series cross‐section analysis is conducted using data from the Comparative Manifestos Project for 19 West European countries from 1980–2010. The findings have important implications for understanding issue evolution in multiparty systems and how and why the dynamics of party competition on the green issue vary across time and space.

Extensive research applies counterfactual simulation methodology to study parties’ optimal policy positions in multiparty elections. In recent years, this methodology has been extended to the study of variation in issue salience. We employ this method to estimate the electoral effects of changes in the salience of specific positional issue dimensions on parties’ success. Applied to British Election Study survey data from 2017 and 2019, we find that plausible issue salience changes could have shifted the parties’ projected vote shares by several percentage points. Our approach implies that the governing Conservative Party had electoral incentives to downplay positional issues, to magnify the relative effects of its non‐policy advantage due to perceived competence and performance, among other factors. Labour would also have benefitted from reduced salience of Left‐Right ideology. By contrast, the Liberal Democrats had strong electoral incentives to emphasize their moderate Left‐Right position.

Party competition in Eastern Europe faces a seeming paradox. On the one hand, research finds increased political volatility in these countries, while, on the other, some authors demonstrate inherent ideological stability in the region. This research note presents a new methodological approach to adjudicating between these two findings, and suggests that while political organisations come and go, the ideological structure of party competition in Eastern Europe is strikingly steady. By developing a number of different measures of the dimensional structure of party competition, the consistency of the measures across countries, as well as their relative stability within countries over time, is demonstrated. The findings speak to current developments in Eastern Europe, and have implications beyond the region. The conclusion that even volatile party systems can be underpinned by stable ideological oppositions points to two different types of party system structure: one related to parties as organisations, and the other related to parties as expressions of political divides.