Primary Concerns: Groups, Parties, and Nominating Challenges in Contemporary Politics

This thesis engages in a critical analysis of polarization, primary challenges, and interest groups in contemporary U.S. politics. The Democratic and Republican Parties have become both increasingly distinct from each other and ideologically extreme in recent decades, and many signs point to a partisan asymmetry with respect to how the two parties are separately contributing to polarization. Moreover, the number of intraparty primary challenges has risen drastically over the past two decades. After evaluating several of the major scholarly debates pertaining to polarization as well as other scholarly literature detailing primary challenges and interest groups, this thesis considers two major questions. First, it discusses and analyzes a series of primary challenges to incumbents in order to determine what variables predict where one would expect to see an ideologically driven primary challenge occur. Second, it outlines and evaluates differences among various types of interest groups in order to determine the source of any discrepancies between the propensity of groups to engage in primary challenges on the political left and the propensity of groups to engage in primary challenges on the political right.