The growth of non-standard employment, such as temporary work, is one of the most important transformations of European labour markets in past decades. For many academic observers, this growth is part of a broader trend towards the “dualisation” of European societies. This means an increasing differentiation between insiders and outsiders with regard to job security and welfare state quality. What are the political repercussions of these developments? How do outsiders react to their exclusion from core social rights? While some contributions stress “rational” responses, such as voting for pro-welfare parties, others stress that social exclusion might come with political exclusion. According to this latter view, outsiders increasingly withdraw from political participation, because they are poorly represented by political elites. Despite this important debate, we still know strikingly little about the actual political behaviour of outsiders. I intend to fill this gap with an empirical analysis of the political behaviour of temporary workers. Based on electoral studies and original survey evidence, I analyse temporary workers’ social policy preferences and the conditions under which these preferences are translated into voting behaviour.