Presidential Coattails in Open-Seat Elections

This study examines the impact of presidential coattails in open-seat races for the U.S. House of Representatives. Although presidential coattails exert a strong influence on congressional vote margins, coattails may have determined whether a party won or lost an open seat in only 34 of 254 races between 1972 and 1992-about 13% of the time. Where coattails are decisive, they seem to help Republicans (who frequently need the help) more than Democrats (who generally do not). Parties must continue to increase the competitiveness of open-seat races before coattails will influence the outcome of a substantial number of contests.