The possible development of a European public sphere is a special challenge for research on transformations of the state in Europe. Undoubtedly, the supranational regime of the European Union (EU) is a major expression of the transformations of the state and the transnationalization of politics in Europe. Current political theory argues that supranational institutions are faced with various legitimation problems (Habermas 2009a; Scharpf 2009). In addition to elections, a functioning ‘public sphere’ is often seen as a prerequisite of political legitimacy.