The postmaterialism thesis contends that newer cultural and social justice issues will supplant traditional, class‐based economic concerns as societies become increasingly wealthy. Although macrolevel evidence broadly supports this prediction, individual‐level evidence for the theory in the United States has been sparse. Moreover, alternative theories predict that postmaterialism will not travel well to the American context because religious cleavages that divide the major parties will be most salient. We test the postmaterialism thesis at the individual level using unique data that enable us to evaluate citizens' value‐preference structures across income levels, as well as the conditional effect of income on the relationship between individuals' ranked value preferences and political attitudes and behavior. Consistent with the theory, greater income strengthens the association between egalitarianism and ideology, partisanship, evaluations of President Obama, and presidential vote choice, and weakens the relationship between moral traditionalism and these same variables. However, income does not moderate the association between economic security and individuals' identities, evaluations, or behavior. Additionally, value‐preference hierarchies are quite similar across income groups after controlling for partisanship and ideology. The results lend insight into the nature of value‐ and income‐based cleavages in American politics.