Gubernatorial Midterm Slumps


  • Olle Folke is Assistant Professor of International and Public Affairs, Columbia University, International Affairs Building, Room 1402, New York, NY 10027 ( James M. Snyder is Professor of Government, Harvard University, 1737 Cambridge St., Cambridge, MA 02138 (

  • We thank Bob Eriksson, Donald Green, and seminar participants at the MIT political economics breakfast, IIES, the American Politics & Public Policy Workshop at Yale University, and the American Politics seminar at Columbia University for their insightful comments on this article. We also thank the editor and anonymous referees for their helpful suggestions. These have significantly improved the article.


This article studies gubernatorial midterm slumps in U.S. state legislative elections. We employ a regression discontinuity design, which allows us to rule out the hypothesis that the midterm slump simply reflects a type of “reversion to the mean” generated by simple partisan swings or the withdrawal of gubernatorial coattails or “anticipatory balancing.” Our results show that the party of the governor experiences an average seat-share loss of about 3.5 percentage points. We also find evidence suggesting that a large share of the variation in gubernatorial midterm slumps can be accounted for by (1) crude partisan balancing and (2) referendums on state economic performance, with approximately equal weight given to each.