This list includes United States senators who switched parties while serving in the Senate.
Senator | State | Date | Congress | Old party | New party | Notes |
---|---|---|---|---|---|---|
James H. Kyle | South Dakota | 1891 | 52nd | Independent | Populist | |
William Morris Stewart | Nevada | 1893 | 53rd | Republican | Silver Republican | The Silver Republicans' seniority and committee assignments were not affected by their having left the party. [1] |
John P. Jones | Nevada | September 4, 1894 | Republican | Silver Republican | ||
Henry M. Teller | Colorado | June 17, 1896 | 54th | Republican | Silver Republican | |
Lee Mantle | Montana | Republican | Silver Republican | |||
Richard F. Pettigrew | South Dakota | Republican | Silver Republican | |||
Frank J. Cannon | Utah | Republican | Silver Republican | |||
Fred Dubois | Idaho | 1896 | Republican | Silver Republican | ||
James H. Kyle | South Dakota | 1897 | 55th | Populist | Republican | |
William Morris Stewart | Nevada | December 4, 1899 | 56th | Silver Republican | Republican |
Senator | State | Date | Congress | Old party | New party | Notes |
---|---|---|---|---|---|---|
Jim Jeffords | Vermont | June 6, 2001 | 107th | Republican | Independent | Caucused with the Democrats |
Joe Lieberman | Connecticut | 2006 | 110th | Democratic | Independent Democrat | Caucused with the Democrats. Lieberman was re-elected on the Connecticut for Lieberman ticket; however, he never formally joined that political party. |
Arlen Specter [2] | Pennsylvania | April 28, 2009 | 111th | Republican | Democratic | Originally a Democrat |
Kyrsten Sinema [3] | Arizona | December 9, 2022 | 117th | Democratic | Independent | Caucused with the Democrats |
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