Thomas E. Mann (born September 10, 1944) is the W. Averell Harriman Chair and a senior fellow in Governance Studies at the Brookings Institution, a non-partisan think tank based in Washington, D.C. He primarily studies and speaks on elections in the United States, campaign finance reform, Senate and filibuster reform, Congress, redistricting, and political polarization.
He was born in Milwaukee, Wisconsin, and attended the University of Florida, where in 1966 he received a B.A. in political science, then went on to get an M.A. (1968) and Ph.D. (1977) at the University of Michigan. He first went to Washington D.C. in 1969, where he worked as a Congressional Fellow in the offices of Senator Philip A. Hart and Representative James G. O'Hara, both Democrats.
Between 1987 and 1999, he was Director of Governance Studies at Brookings. Before that, Mann was executive director of the American Political Science Association.
Mann is a fellow of the American Academy of Arts and Sciences and a member of the Council on Foreign Relations. He is a recipient of the American Political Science Association’s Frank J. Goodnow and Charles E. Merriam Awards.