Pfizer-Pratt University Professor of Political Science. He specializes in American politics and behavior, formal theory, and methodology. Books he has authored or co-authored include Why Parties, Before the Convention, Linear Probability, Logit and Probit Models, and a series of books on elections, the most recent of which is Change and Continuity in the 2008 and 2010 Elections. His articles have appeared in the American Political Science Review, American Journal of Political Science, Journal of Politics, Public Choice, and other journals and edited volumes. He has received grants from the National Science Foundation and the National Endowment for the Humanities, and has served as co-editor of the American Journal of Political Science and as a Fellow at the Center for Advanced Study in the Behavioral Sciences. Current projects include studies of various aspects of campaigns and elections, political parties, and Congress. He is currently President of the American Political Science Association.