This paper aims to explain the electoral performance of populist parties in Europe, using Qualitative Comparative Analysis (QCA) techniques. Throughout the past decades many European countries have witnessed an increase in the electoral support for populist parties. Although these parties have received substantial scholarly attention, most accounts have, so far, focused on Western European radical-right variants. This paper broadens the scope by taking into consideration 31 European countries, including post-communist countries in Central and Eastern Europe. It tests whether (a combination of) the following causal conditions is related to the electoral success or failure of populist parties: the availability of the electorate, the electoral system, the responsiveness of the established parties and the supply of credible populist challengers. Although not many comparative analyses take the agency of populist parties themselves into account, especially this latter factor is expected to be crucial to the electoral performance of populist parties.
