This article addresses two aspects of social network influence on voters’ electoral choices that are not well understood: the role of party systems as institutional contexts and the relationship between social pressure and information sharing as mechanisms of influence. It argues that in the cleavage-based multiparty systems of Western Europe, discussant influence at elections occurs in two stages. First, discussants place social pressure on voters to opt for parties from the same ideological camp. Secondly, by providing information, discussants influence which parties voters eventually choose out of these restricted ‘consideration sets’. The study tests these assumptions using a panel survey conducted at the 2009 German federal election. The first proposition is clearly confirmed, and the evidence supports the second proposition, although less unequivocally.
British Journal of Political Science