One Tick and You're Out: the Effects of the Master Lever on Senator Positions

Abstract: This paper accounts for the effects of the master lever (ML), aka the straight-ticket voting option, on the positions of US senators from 1960 till 2010. The master lever is an option offered in ballots in some US states allowing voters to vote for a specific party for all offices listed, by selecting a box at the top, as opposed to filling out each one individually. Introducing a master lever leads to more people voting by the party affiliation of the senatorial candidate as opposed to her position. This shifts the groups of voters targeted by the parties and thus the positions of elected senators. We build a theory of multidimensional pre-election competition to understand these incentives. Empirically, we use a triple difference estimator to account for selection into the three treatment groups (ML always, ML never, ML then no ML) and compare the results to the theoretical predictions. We find that the presence of the master lever is a significant determinant of senatorial positions. It leads to more moderate or more extreme senators depending on the partisanship of the state, the preferred policy positions of the average voter and the correlation between the two in the state.