How do at-large elections affect electoral competition? This paper shows that the adoption of single-member districts in local elections in California caused the supply of candidates to drop, making competitive elections less likely and increasing the share of incumbents who faced no challenger....

We analyze the effect of turnout requirements in referenda in the context of a group turnout model. We show that a participation quorum requirement may reduce the turnout so severely that it generates a "quorum paradox": in equilibrium, the expected turnout exceeds the participation quorum only...