Andrew Hall - Polarization and State Legislative Elections

Andrew Hall, Professor of Political Science, Stanford University
Encina Hall West, Room 400 (Graham Stuart Lounge)
Andrew Hall

U.S. state legislatures are critical policymaking bodies and the major pipeline of candidates to national office. Polarization in state legislatures has increased substantially in recent decades, yet we understand little about the role of elections in this process. We offer the first systematic study of state legislative candidate ideology across all election stages using a new dataset on primary- and general-election results for over 100,000 candidates, 1992-2020. To measure candidate ideology, we use machine learning to predict roll-call-based scores of ideology from millions of campaign contribution records. We find that the pool of candidates has polarized substantially in recent decades, while electoral competition has been consistently low. More-extreme candidates have enjoyed a modest advantage in contested primaries, and this advantage has doubled in the past decade. More-moderate candidates have enjoyed an advantage in contested general elections, but this has shrunk to nearly zero in the last decade. The results indicate a shifting equilibrium in which more-extreme candidates increasingly seek office, win primaries more often, lose general elections less often, and face limited competition. 


Andrew Hall is a Professor of Political Science and, by courtesy, a Professor of Political Economy at the Graduate School of Business. He is the co-director of the Democracy & Polarization Lab and a Senior Fellow at the Stanford Institute for Economic Policy Research. Currently, Hall’s research group is focused on understanding how to preserve democracy and safely administer elections in the time of COVID-19, how to reduce or manage political polarization, and how state and local governments in the United States can become more dynamic and better able to grow, build, and innovate.