This volume explores the development of political parties in nineteenth-century United States of America through an extensive analysis of the official statements by a party in an election, the party platforms, and their connection with political elites and voters. Platforms indicate how party leaders reconciled local, state, and national conflicts and articulated their electoral appeals to various constituencies by showing discussions of their respective policies. Thus, party platforms are a valuable vehicle to assess electoral strategy and party development. By focusing on the platforms of the major political parties-Democrats, Whigs, and Republicans-at the state and national levels in presidential elections from 1840 to 1896, the author identifies three salient patterns. First, platforms reference economic policy more frequently and to a greater degree than other policy areas. Second, national policies are discussed more than state policies. And third, over time, the content of the platforms becomes more similar, reflecting the nationalization of the party system. This examination of nineteenth-century American party platforms traces political party development as a dynamic process involving partisanship, the presentation of internally coherent and consistent messages to voters, and polarization, the existence of conflicting policy positions across parties.