The Collaborative International Dictionary of English v.0.48:

Dixiecrats \Dixiecrats\ n.
   a former political party in the US; formed in 1948 by
   Southern Democrats opposed to the candidacy of Harry S.
   Truman.

   Syn: States' Rights Democratic Party.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

Dixiecrats
    n 1: a former political party in the United States; formed in
         1948 by Democrats from southern states in order to oppose
         to the candidacy of Harry S Truman [syn: States' Rights
         Democratic Party, Dixiecrats]