Shaping parties’ legitimacy: Internal regulations and membership organisations in post-communist Europe

For more than two decades post-communist political parties have sought to increase their popular legitimacy. The membership organisation is one way to achieve this goal, but its size varies considerably across parties. This article contributes to research on the causes of membership variation by analysing the effects of party statute regulations. In doing so, it controls for previous explanations such as age, ideology, incumbency, and electoral support. The analysis focuses on 28 parliamentary parties from six Eastern European countries between 2005 and 2008, using qualitative content analysis and statistics. The empirical evidence supports the expectation that political parties with more regulations benefit from having larger membership organisations. The multivariate analysis shows statute provisions to be the second-best predictors of membership size