Exploring Party Cohesion among the Party on the Ground: The Impact of Party Activists’ Social Networks on the Cohesion of their Local Party Branch

Party cohesion has been mainly studied from the perspective of the party in public office (Andeweg & Thomassen 2010, Sieberer 2006, Katz et al. 1999), while cohesion within the party on the ground has remained largely under-studied. Yet local party branches constitute an important organizational component of parties. They are not homogeneous entities: they integrate party members who do not always share the same ideological stances, do not support the same candidates or leaders in internal elections, do not participate in the same type of party activities, or do not display the same level of satisfaction regarding how their party functions. In this paper, we investigate the determinants of cohesion in local party branches. We argue that the structure of social networks at the local level conditions how party members think and behave within their party, and thereby the level of internal cohesion. The empirical analysis relies on a survey conducted among activists of 7 local party branches of 4 Belgian political parties. We identify the patterns of social relationships among party activists in each local branch (centrality, density, clustering coefficient, etc.). We relate this to levels of internal cohesion measured both as ideological cohesion and level of satisfaction within the branch. In doing so, this paper highlights the added value of Social Network Analysis in the analysis of party cohesion and intra-party dynamics.