The effect of party primaries on electoral performance

One of the most relevant issues linked to party democratization to be researched is the consequences of more inclusive methods of candidate selection, and particularly of primaries, on party competition. To approach this issue implies to analyse whether or not the use of primaries make the parties more competitive. In spite of the relevance of the issue, and contrary to the attention it has received in US, it has rarely been analyzed in Europe. What we intend to do in this article is to analyse if the use of one member one vote (OMOV) primaries for candidate selection affects the electoral result of the party and, if it does, in what direction. In this way, we will increase our still limited knowledge of this aspect of European party politics through the analyses of the use of closed party primaries in the Spanish Workers Socialist Party (PSOE) and their effects on its electoral performance in local elections. Therefore, this paper has two main goals. The first one is to describe the use of party primaries in the selection of candidates for local elections by the PSOE and its evolution. The second and main one is to answer the question on the effect of party primaries on electoral performance studying the case of the Spanish Socialists in the 1999, 2003, 2007 and 2011 local elections.