Electoral competition and endogenous barriers to entry

•Entry barriers have been tightened in response to stronger electoral competition.•Ballot access laws regulate the access of candidates to elections in the US.•The stringency of ballot access laws varies across states and time.•The Voting Rights Act of 1965 provides exogenous variation in electoral competition.

As institutions matter for political and economic outcomes, they are (at least partly) shaped by the interests of political agents acting under these limitations. However, empirical evidence documenting such endogenous change of institutions is scarce. We address the issue by examining the link between the degree of electoral competition and the design of ballot access restrictions in the United States. Exploiting exogenous variation in electoral competition at the state level induced by the federal Voting Rights Act of 1965, our main finding is that ballot access rules have been systematically tightened in response to stronger electoral competition.