James Adams is Associate Professor of Political Science at the University of California, Santa Barbara. His primary research interest is the application of spatial modeling to real world elections, and the insights this approach can provide into theories of political representation. He is the author of Party Competition and Responsible Party Government: A Theory of Spatial Competition Based upon Insights from Behavioral Voting Research (2001), as well as articles in the American Journal of Political Science, the Journal of Politics, the British Journal of Political Science, and Public Choice.

Samuel Merrill, III, is a Professor of Mathematics and Computer Science at Wilkes University, Pennsylvania. He received a PhD from Yale University, Connecticut. His current research involves mathematical and statistical modeling, particularly in political science. He is the author (with Bernard Grofman) of A Unified Theory of Voting (Cambridge, 1999) and Making Multicandidate Elections More Democratic (1988) and has published in a number of journals including the American Political Science Review, the American Journal of Political Science, and the Journal of the American Statistical Association. He has been a visiting professor at Yale University and a visiting scholar at the University of Washington.

Bernard Grofman is Professor of Political Science (and adjunct Professor of Economics) at the University of California, Irvine. He received his PhD in Political Science from the University of Chicago in 1972. He is an expert on comparative election systems and models of voting, and social choice theory. He has published over 200 articles in journals such as the American Political Science Review, the American Journal of Political Science, Electoral Studies, and Public Choice, and he has authored or co-edited seventeen books. He has been a Fellow of the Center for Advanced Study in the Behavioral Sciences at Stanford, a visiting professor at the University of Michigan, the University of Washington, and the University of Mannheim, and a scholar-in-residence at the University of Bologna, Kansai University, Osaka, the German Science Center, Berlin, Pompeu Fabra University, Barcelona and the Brookings Institution, Washington DC. He is past president of the Public Choice Society and a Fellow of the American Academy of Arts and Sciences.

This book integrates spatial and behavioral perspectives - in a word, those of the Rochester and Michigan schools - into a unified theory of voter choice and party strategy. The theory encompasses both policy and non-policy factors, effects of turnout, voter discounting of party promises, expectations of coalition governments, and party motivations based on policy as well as office. Optimal (Nash equilibrium) strategies are determined for alternative models for presidential elections in the US and France, and for parliamentary elections in Britain and Norway. These polities cover a wide range of electoral rules, number of major parties, and governmental structures. The analyses suggest that the more competitive parties generally take policy positions that come close to maximizing their electoral support, and that these vote-maximizing positions correlate strongly with the mean policy positions of their supporters.