The Department of Political Science is proud to announce that Ph.D. student Wataru Onishi was awarded a Spring 2025 Centennial Center Research Grant earlier this year from the American Political Science Association (APSA) for his project, “Can Intra-Party Disagreement Mitigate Affective Polarization?”

Over the past decade, Americans have grown increasingly hostile toward members of the opposing political party. Many citizens not only disagree across party lines but also feel anger, distrust, and resentment—an emotional division known as affective polarization. This trend has become a serious concern for the health of democracy, as it undermines civic cooperation and cross-partisan understanding.

While prior research has largely focused on how national leaders—such as presidential candidates—contribute to this divide, Onishi’s work asks a critical but underexplored question: What role do rank-and-file members of Congress play in shaping partisan animosity?

To answer this, Onishi will use his APSA Centennial Center funding to conduct a survey experiment testing whether exposing citizens to intra-party disagreement can reduce affective polarization.

Onishi aims to assess whether highlighting internal diversity within political parties can help citizens see opponents in a less hostile light—and whether party leaders’ influence might amplify or limit that effect.

Onishi explained that this “research serves the public by clarifying the importance and limitations of different types of politicians in shaping affective polarization." His findings will shed light on how ordinary members of Congress—not just party elites—can either reinforce or reduce emotional divides in American politics.