Jacobson's field of interest is American national politics, with a subfield focus on Congress and congressional elections. He is the author of Money in Congressional Elections; The Politics of Congressional Elections (currently in its 6th edition); and The Electoral Origins of Divided Government; and co-author of Strategy and Choice in Congressional Elections, American Parties in Decline, and The Logic of American Politics. His current research is on the electoral basis of partisan polarization in Congress. He has served on the Council of the American Political Science Association and as its Treasurer. He is a fellow of the American Academy of Arts and Sciences. From 1985 through 1993 he served on the Board of Overseers of National Election Studies, which designs the biennial election surveys conducted by the University of Michigan's Center for Political Studies. During 1990-91 he was a Fellow at the Center for Advanced Study in the Behavioral Sciences.