Party survival in parliament: Explaining party durability in lower-house parliaments

Approximately 70 per cent of the parties emerging in the post-Second World War era failed to keep their seats in parliament. Party survival is an important issue, especially in parliamentary democracies, where parties are the means through which voters’ preferences are linked to government policy outputs. Using an event history modeling framework, and data from 37 democracies, covering 830 parties, this article analyses two questions regarding party durability. First, when do parties fail? Second, which parties survive longer? The article shows that most parties fail at the beginning of their lifespan, and disappear before the end of their fourth term in parliament. Moreover, it is found that moderate policy position, distinct ideology and participation in governing coalitions increase the duration of party survival, even when controlling for party size. This article contributes to the extensive literature about the electoral benefits of ideological moderation and distinct policy positions by showing the long-term benefits of these factors. Moreover, the long-term benefit of party participation in government in terms of survival overcomes the short-term cost of ruling.