Before Their Time: How the Timing of Democratisation Affects Challenger Party Euroscepticism

When do challenger parties mobilise Euroscepticism? The literature has assumed that European integration is always a new issue, orthogonal to the dominant dimension of competition. Since they were founded on previous conflicts and have social constituencies and issue reputations that precede it, dominant parties are internally split on this issue. This enables challenger parties to mobilise opposition to European integration as a wedge issue later on. While in agreement with this logic of party competition, I question this assumption. Democratisation should be seen as a critical juncture with regard to party system dimensionality, as the timing of democratisation relative to the process of European integration enables or precludes issue politicisation. When party system formation took place after the onset of the European project (as in Third Wave democracies), dominant parties could take stances on European integration. This means they could form their constituencies and reputations partly on its basis, subsuming it under an existing dimension of competition and hindering its later mobilisation by challenger parties. Yet this holds only for as long as these ‘founding generation’ parties continue to structure the political space. The extent to which issues mobilised during democratisation are bundled into stable dimensions will be limited in weakly institutionalised party systems, with short-lived dominant parties and uninformative party labels. In party systems that were sufficiently well-institutionalised during democratisation, the degree to which European integration was emphasised in the same period should thus moderate the effect of being a challenger party on current party positions on the EU. This is tested in a mixed methods setting. Quantitatively, I predict parties’ current EU positions (from the Chapel Hill Expert Survey) as a function of their dichotomous past government participation interacted with the country-wise salience of European integration during democratisation, estimated using Manifesto Project data, and electoral volatility in the same period. As theorised, under low early volatility, the marginal effect of past government participation (i.e., the gap between challenger and dominant parties’ EU positions) decreases and eventually disappears as early salience increases. Two case studies complement this analysis, discussing the moderating role of party system institutionalisation. In the well-institutionalised Portuguese party system, the dominant parties date to the democratic transition, when they adopted clear positions on European integration, preventing it from becoming a wedge issue or being mobilised by challengers like Chega. In Poland, by contrast, profound instability during democratisation entailed short-lived parties, eroding the formation of lasting alignments and allowing the successful mobilisation of Euroscepticism by challenger parties. This paper contributes to a better understanding of the ideological appeals of challenger parties, refining existing accounts of issue entrepreneurship while underlining the usefulness of the challenger party concept. It also reinforces the importance of the historical process of democratisation and party system formation in explaining party system dimensionality, suggesting that historical legacies matter not merely in explaining intra-country voting patterns but cross-national variation in the structure of party competition.