No hard feelings? The effects of competition on vote transfers in two-round elections

Abstract Runoff elections are a useful method for solving coordination problems in majoritarian electoral systems based on single-member districts in that they provide a formal mechanism for ideologically similar parties to coordinate on a single candidate. The mechanism is, however, not free of problems as it places ideological neighbors in competition with one another on the first ballot. The temptation to campaign against the members of one’s own bloc carries risk, as it may reduce the willingness of the supporters of the losing party on the first ballot to cast their vote for the party that will represent its ideological bloc on the second ballot. We revisit and extend Tsebelis’ (Br J Polit Sci 18(2):145–70, 1988a) work on the conditions under which parties are able to curb their incentives to engage in intra-bloc campaigning by deriving additional testable hypotheses and expanding the analysis temporally to include elections from 1958 to 2012.