Abstract
In recent decades, partisan polarization has not only grown but also extended to a wide variety of political processes. Despite this fact, we lack a strong understanding of the policy process under conditions of relatively extreme polarization. The roles of interest groups and think tanks in this environment are particularly understudied. How have research producing institutions changed in response to partisan polarization? And which types of organizations are most influential under the current system? Existing theories often lack an appreciation of the role of partisanship and assume relatively unstructured pluralistic competition in the development and debate of public policy. To help rectify this limitation, I view actors in the policy process as part of a system structured mainly by partisan dynamics. This changing “marketplace for ideas” has incentivized some interest groups and think tanks to invest in a single political party to enhance their influence and accomplish their goals. The result is a policy system defined by two competing extended party networks, or loose coalitions of formal party members and outside research institutions. Under such conditions, influence accrues to those organizations that engage in relatively partisan research and advocacy efforts.