The Democratic Party is a coalition of social groups that act as discrete voting blocs for candidates, constituencies for group leaders, and demanders of particular policy commitments. Since the 1960s, the evolution in the relative internal influence of Democratic Party constituencies has reduced the size of the party’s conservative wing and expanded its policy agenda—but no organized liberal movement has emerged to dominate its internal organization or succeed in shifting its policies toward leftist positions. The Republican Party, in contrast, serves as the vehicle of a conservative ideological movement that has succeeded in fusing its intellectual strands, marketing its broad critiques of government, building a supportive organizational network, and moving the party toward the policy commitments of its right wing. This underlying party asymmetry produces distinct Democratic and Republican approaches to debating public issues, campaigning for votes, and pursuing policy change in government. The concurrent operational liberalism and symbolic conservatism of the American public allows each party to maintain its unique character while effectively competing for broader popular support.