The explanation of the emergence and consolidation of democratic regimes is one of the most important copies of political sociology. The main theoretical approaches can be divided into actor- and elite-theories on the one hand and structure- and modernization-theories on the other. This article combines actor- and structure-centered theories following the discussion of Lipset's thesis of the connection between socio-economic modernization and democracy. Its theoretical starting point is the assertion that the emergence and consolidation of democratic regimes can be explained with reference to the power resources and interests of collective actors. These are determined in two ways by structural conditions: first, the social structural basis for the mobilization of collective actors changes with socio-economic modernization processes. Second, the mobilization of actors is dependent on certain conditions, which are influenced by modernization processes. The role of the state is emphasized, because the state can strongly affect the conditions of mobilization for collective actors in the civil society, and therefore block processes of democratization. The interests and power resources of state elites are nor only conditioned by endogenous modernization processes, but furthermore by exogenous, geopolitical conditions. Therefore, the final result is, that socioeconomic modernization processes are a necessary but not sufficient condition for democratization.