Primaries Push Extremes; General Elections Still Favor Moderates

Why State Legislative Polarization Matters

U.S. state legislatures shape policy on education, criminal justice, health, and more, but researchers have struggled to measure how elections at the state level contribute to growing ideological divides. Cassandra Handan-Nader, Andrew C. W. Myers, and Andrew B. Hall tackle this measurement gap to show how candidate selection and electoral outcomes interact with polarization across 2000–2022.

What Handan-Nader, Myers, and Hall Did

The authors build new candidate-level measures of ideology and use them to examine every contested primary and general election for state legislative seats from 2000 to 2022. This is presented as the first systematic study linking candidate ideology to electoral outcomes across U.S. state legislatures over this period.

How Ideology Was Measured

• The team derives candidate ideology from two complementary sources: patterns in campaign contributions and roll-call voting records.
• Combining these signals produces a candidate-level ideological placement that can be compared across elections and over time, addressing prior data limitations in lower-salience, lower-information contests.

Key Findings

• The pool of people running for state legislative office has become substantially more polarized over the past two decades.
• In contested general elections, more-moderate candidates still enjoy a meaningful electoral advantage, although that moderation advantage has declined somewhat in recent years.
• Contested primary elections tend to favor more-extreme candidates, producing a divergence between who wins primaries and who is competitive in generals.

What This Means for Research and Policy

These new measures and the authors' empirical mapping of 2000–2022 elections create a platform for future work on candidate selection, legislative behavior, and electoral accountability in low-information settings. By making candidate ideology tractable at scale, the study helps explain one mechanism behind state-level polarization and points to where reforms or strategic responses (e.g., primary rules, candidate recruitment) might change electoral incentives.