UCLA

This dissertation is about how political parties formed in the world's first mass democracy, the United States. I trace the process of party formation from the bottom up. First, I ask: How do individuals become engaged in politics and develop political affiliations? In most states, throughout the antebellum era, the county was the primary unit of political administration and electoral representation. Owing to their small size, contiguity, and economic homogeneity, I expect that each county's active citizens will form a county-wide governing coalition that organizes and dominates local politics. Second, I ask: Which political actor had incentives to lure county organizations into one coalition? I argue that the institutional rules for electing United States Senators - indirect election by state legislature - induced prospective United States Senators to construct a majority coalition in the state legislature.

Drawing on nineteenth century newspapers, I construct a new dataset from the minutes of political meetings in three states between 1820 and 1860. I find that United States Senators created state parties out of homogeneous counties. They encouraged cooperation among

county-wide governing coalitions by canvassing annual county political meetings, drafting and revising a multi-issue policy platform that had the potential to unite a majority of the state's county governing coalitions, encouraging individual counties to create county-wide committees of correspondence and vigilance, and, finally, organizing a permanent state central committee and regular state-wide conventions. I also show that alternative political actors lacked the incentives, resources, and long-term policy view necessary to build a state- wide party.

I conclude by considering the implications of this argument for debates about the nature of partisan affiliation, party cohesion, the formation of policy agendas, and the linkage between the mass public and the national government in a federal system.