Electoral competition with primaries and quality asymmetries

We introduce primaries—both closed and open—into a Downsian model of two-party electoral competition allowing the two candidates in each party’s primary to differ in valence as well as in policy platform. The good news is that the introduction of either type of primary acts as a stabilizing force since equilibriums exist quite generally, serves as an arena for policy debates since all candidates propose differentiated platforms, and guarantees that each party’s nominee is of higher quality than its primary opponent. Moreover, primaries tend to benefit the party whose median voter is closer to the overall median. The bad news is that the winner of the general election need not be the candidate with the highest overall quality since primaries that are too competitive can prove harmful. Given the differences between open and closed primaries, we show that the choice of primary type is particularly important and may determine the winner of the general election.