Steven S. Smith, Washington University, St Louis Steven S. Smith is a Professor of Political Science, the Kate M. Gregg Distinguished Professor of Social Science, and Director of the Murray Weidenbaum Center on the Economy, Government, and Public Policy at Washington University, St Louis. He has chaired the Legislative Studies Section of the American Political Science Association and has served on the editorial boards of the American Journal of Political Science, The Journal of Politics, and Legislative Studies Quarterly. Jason M. Roberts, University of North Carolina, Chapel Hill Jason M. Roberts is an Associate Professor of Political Science at the University of North Carolina, Chapel Hill. He co-edited the book Why Not Parties? Party Effects in the US Senate (2009). His articles have been published in the American Political Science Review, the American Journal of Political Science, and Legislative Studies Quarterly. Ryan J. Vander Wielen, Temple University, Philadelphia Ryan J. Vander Wielen is an associate professor of Political Science at Temple University, Philadelphia. His articles have been published in the American Political Science Review, the American Journal of Political Science, and Legislative Studies Quarterly, Political Analysis, Legislative Studies Quarter, Public Choice, and Political Research Quarterly.