Federalism and the European party system

Applying a framework from comparative federalism to the European party system requires examining the ways in which the European and national party systems are linked, through congruent or incongruent party system structures and through party organizations that either integrate or separate the two arenas of political competition. The European party system exhibits two forms of incongruence. The first is a high degree of party strength in some national party systems for parties that lie outside the ideological range of the core party families in the European Parliament. The second is the emergence of parties that compete only in European parliamentary elections on European issues, signalling the politicization of a European integration cleavage.