This article tests a variation of the “carryover” hypothesis that hotly contested races for the presidential nomination often translate into increased levels of nonvoting and defection in the general election. Probit analysis of data from the 1988 American National Election Study suggests that independents who supported Gore or Robertson were less likely to vote than those who supported Bush or Dukakis. Voter turnout among partisans appears unaffected by prenomination preferences. Defection to the opposition party's candidate was, however, more frequent among Democratic backers of Gore and Hart, independents who supported Gore, and independents who supported Dole, Robertson, or Kemp. Republicans remained loyal to the Bush ticket regardless of their prenomination preferences. These findings suggest that hotly contested nominations often hurt the party in November, particularly among Democrats. We conclude with a discussion of recent Democratic party reforms which have attempted to lessen the likelihood of such party disunity.