Political psychology has paid rather little attention to personality traits when explaining political attitudes and political behavior in mass publics. The present paper argues that personality traits contribute to our understanding of political attitude formation and decision making of ordinary citizens. Based on the Five Factor Model of Personality, we state hypotheses regarding the effects of personality traits on partisan attitudes and vote choice in Germany. We test the hypotheses using survey data obtained from a random sample of the Germans eligible to vote. The evidence confirms that personality traits indirectly affect partisan attitudes and voting behavior in Germany in predictable ways even after controlling for sociodemographic characteristics. More specifically, Openness makes citizens more inclined to support parties endorsing social liberalism whereas low scores on Conscientiousness increase the likelihood of liking and voting for parties subscribing to economic or social liberalism as do high levels on Agreeableness. High levels of Neuroticism appear to promote support for parties that offer shelter against material or cultural challenges.