We consider the effect of legislative primaries on the electoral performance of political parties in a new democracy. While existing literature suggests that primaries may either hurt a party by selecting extremist candidates or improve performance by selecting high valence candidates or improving a party’s image, these mechanisms may not apply where clientelism is prevalent. A theory of primaries built instead on a logic of clientelism with intra-party conflict suggests different effects of legislative primaries for ruling and opposition parties, as well as spillover effects for presidential elections. Using matching with an original dataset on Ghana, we find evidence of a primary bonus for the opposition party and a primary penalty for the ruling party in the legislative election, while legislative primaries improve performance in the presidential election in some constituencies for both parties.