Explaining territorial inequalities in regionalist party strength in European Parliament elections

The electoral strength of regionalist parties in regional and national elections has been studied extensively whereas their electoral strength in European elections have received scant attention (Jolly 2015). This lack of scholarly attention is surprising considering that regionalist parties have many reasons to win seats in the European Parliament (Massetti and Schakel 2020). The EU’s internal market allows secessionist parties to achieve ‘independence in Europe’, the EU can act as a potential ally in the struggle of regionalist parties against the state, nearly 70% of EU legislation is implemented by local and regional authorities, and the EU can be an important source of regional finance through its Cohesion Policy (Schakel and Massetti 2020). We argue that the electoral strength of regionalist parties in EP elections depends mostly on the permissiveness of Europe’s multilevel electoral system. We hypothesize that the spill-over of regionalist party strength from regional and national elections into European elections depends on the differences in how easy it is to win a European seat relative to winning a regional or national seat. In addition, we hypothesize that spill-over increases according to the timing of the European election vis-à-vis the regional and national election cycles. EP elections can be conceived to be third-order elections (Schakel 2018, 2021) and regionalist parties may find it easier to mobilize voters when EP elections take place around-mid-term of the regional or national election cycle. We test our hypotheses using a dataset that includes the vote shares won by 175 regionalist parties in European and previously held regional and national elections held in 67 regions and 10 West European countries since the first EP election of 1979. We find that strength in European elections is highly dependent on the permissiveness of the national but not regional electoral system. However, national electoral strength is, in turn, highly dependent on the permissiveness of the regional electoral system. In addition, we find that timing of the EP election vis-à-vis the regional but not national election matters for spill-over. These results are important because they reveal that there is a large territorial variation in the permissiveness of Europe’s multilevel electoral systems across the EU member states and the regions within them.