Between National Polarization and Local Ideology: The Impact of Partisan Competition on State Medicaid Expansion Decisions

The U.S. Supreme Court’s decision to grant states the authority to reject Medicaid expansion under the Affordable Care Act without penalty threatened the implementation of this polarized health policy. While many Republican-controlled states followed their national allies and rejected Medicaid expansion, others engaged in bipartisan implementation. Why were some Republican states willing to reject the national partisan agenda and cooperate with Democrats in Washington? I focus on the role of electoral competition within states. I conclude that although electoral competition has been shown to encourage partisan polarization within the states, the combination of intergovernmental implementation and Medicaid expansion’s association with public welfare reverses this dynamic. I employ a Cox proportional-hazards model to examine the impact of state partisan ideology and competition on the likelihood of state Medicaid expansion. I find that strong inter-party competition mitigates the impact of more extreme partisan ideologies, encouraging potentially bipartisan negotiation with the federal administration.