Exploiting Friends-and-Neighbors to Estimate Coattail Effects

Federalist democracies often hold concurrent elections for multiple offices. A potential consequence of simultaneously voting for multiple offices that vary with respect to scope and scale is that the personal appeal of candidates in a high-profile race may affect electoral outcomes in less salient races. In this article I estimate the magnitude of such coattail effects from governors onto other concurrently elected statewide executive officers using a unique dataset of county election returns for all statewide executive office elections in the United States from 1987 to 2010. I exploit the disproportionate support that candidates receive from geographically proximate voters, which is often referred to as the friends-and-neighbors vote, to isolate variation in the personal appeal of candidates. I find that a one-percentage-point increase in the personal vote received by a gubernatorial candidate increases the vote share of their party's secretary of state and attorney general candidates by 0.1 to 0.2 percentage points. In contrast, personal votes for a secretary of state or attorney general candidate have no effect on the performance of their party's gubernatorial candidate or other down-ballot candidates.