Social identification among political party voters and members: an empirical test of optimal distinctiveness theory.

According to optimal distinctiveness theory, minority political parties and parties of intermediate size provide more central and important bases of social identity. The authors tested that prediction in a sample of voters and a sample of political party members. In both samples, adherents of minority and intermediate parties did not perceive their parties to be more representative of them. The authors found no significant differences between political parties on the collective self-esteem questionnaire administered to the sample of political party members.