Coattail effects and turnout: Evidence from a quasi-experiment

All over the world, a very large number of elections take place concurrently with other elections for representatives in different government tiers. A crucial question for understanding electoral outcomes in those elections is the existence of electoral spillovers or coattail effects. Causal identification of coattail effects is challenging because popularity shocks typically affect parties in both concurrent elections. This paper exploits a quasi-experiment—the ban of a party in only one of the concurrent elections—to estimate coattail effects. The results show that a 1 pp decline in electoral support for a party in a given election reduces its support in the concurrent election by 0.25 pp. This comes along with a decline in turnout of the same size in both elections.