| Class 1Class 1 U.S. senators belong to the electoral cycle that has recently been contested in 2000, 2006, 2012, and 2018. The next election will be, in 2024.
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C
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Class 3Class 3 U.S. senators belong to the electoral cycle that has recently been contested in 2004, 2010, 2016, and 2022. The next election will be in 2028.
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| #
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Senator
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Party
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Dates in office
|
Electoral history
|
T
|
T
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Electoral history
|
Dates in office
|
Party
|
Senator
|
#
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| Vacant
|
May 29, 1848 –
Jun 8, 1848
|
Wisconsin elected its senators 10 days after statehood.
|
1
|
30th
|
1
|
Wisconsin elected its senators 10 days after statehood.
|
May 29, 1848 –
Jun 8, 1848
|
Vacant
|
| 1
|
Henry Dodge
|
Democratic
|
Jun 8, 1848 –
Mar 3, 1857
|
Elected in 1848.
|
Elected in 1848.
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Jun 8, 1848 –
Mar 3, 1855
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Democratic
|
Isaac P. Walker
|
1
|
| 31st
|
2
|
Re-elected in 1849.Retired.
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| Re-elected in 1851.Retired.
|
2
|
32nd
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| 33rd
|
| 34th
|
3
|
Elected in 1854.
Retired.
|
Mar 4, 1855 –
Mar 3, 1861
|
Republican
|
Charles Durkee
|
2
|
| 2
|
James R. Doolittle
|
Republican
|
Mar 4, 1857 –
Mar 3, 1869
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Elected in 1857.
|
3
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35th
|
| 36th
|
| 37th
|
4
|
Elected in 1861.
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Mar 4, 1861 –
Mar 3, 1879
|
Republican
|
Timothy O. Howe
|
3
|
Re-elected in 1863.
Retired.
|
4
|
38th
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| 39th
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| 40th
|
5
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Re-elected in 1866.
|
| 3
|
Matthew H. Carpenter
|
Republican
|
Mar 4, 1869 –
Mar 3, 1875
|
Elected in 1869.Lost re-election.
|
5
|
41st
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| 42nd
|
| 43rd
|
6
|
Re-elected in 1872.Lost re-election.
|
| 4
|
Angus Cameron
|
Republican
|
Mar 4, 1875 –
Mar 3, 1881
|
Elected in 1875.Retired.
|
6
|
44th
|
| 45th
|
| 46th
|
7
|
Elected in 1879.Died.
|
Mar 4, 1879 –
Feb 24, 1881
|
Republican
|
Matthew H. Carpenter
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4
|
|
|
Feb 24, 1881 –
Mar 14, 1881
|
Vacant
|
| 5
|
Philetus Sawyer
|
Republican
|
Mar 4, 1881 –
Mar 3, 1893
|
Elected in 1881.
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7
|
47th
|
| Elected to finish Carpenter's term.Retired.
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Mar 14, 1881 –
Mar 3, 1885
|
Republican
|
Angus Cameron
|
5
|
| 48th
|
| 49th
|
8
|
Elected in 1885.Lost re-election.
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Mar 4, 1885 –
Mar 3, 1891
|
Republican
|
John Coit Spooner
|
6
|
| Re-elected in 1887.Retired.
|
8
|
50th
|
| 51st
|
| 52nd
|
9
|
Elected in 1891.Lost renomination.
|
Mar 4, 1891 –
Mar 3, 1897
|
Democratic
|
William F. Vilas
|
7
|
| 6
|
John L. Mitchell
|
Democratic
|
Mar 4, 1893 –
Mar 3, 1899
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Elected in 1893.Retired.
|
9
|
53rd
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| 54th
|
| 55th
|
10
|
Elected in 1897.
|
Mar 4, 1897 –
Apr 30, 1907
|
Republican
|
John Coit Spooner
|
8
|
| 7
|
Joseph V. Quarles
|
Republican
|
Mar 4, 1899 –
Mar 3, 1905
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Elected in 1899.Retired.
|
10
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56th
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| 57th
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| 58th
|
11
|
Re-elected in 1903.Resigned.
|
| 8
|
Robert M. La Follette
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Republican
|
Jan 4, 1906 –
Jun 18, 1925
|
Elected in 1905.Did not assume office until Jan 4, 1906 after resigning as Governor of Wisconsin.
|
11
|
59th
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| 60th
|
|
|
Apr 30, 1907 –
May 17, 1907
|
Vacant
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| Elected to finish Spooner's term.
|
May 17, 1907 –
Mar 3, 1915
|
Republican
|
Isaac Stephenson
|
9
|
| 61st
|
12
|
Re-elected in 1909.Retired.
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| Re-elected in 1911.
|
12
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62nd
|
| 63rd
|
| 64th
|
13
|
Elected in 1914.Died.
|
Mar 4, 1915 –
Oct 21, 1917
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Democratic
|
Paul O. Husting
|
10
|
| Re-elected in 1916.
|
13
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65th
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|
|
Oct 21, 1917 –
Apr 18, 1918
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Vacant
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| Elected in 1918 to finish Husting's term.
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Apr 18, 1918 –
Mar 3, 1927
|
Republican
|
Irvine Lenroot
|
11
|
| 66th
|
| 67th
|
14
|
Re-elected in 1920.Lost renomination.
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| Re-elected in 1922.Died.
|
14
|
68th
|
| 69th
|
| Vacant
|
Jun 18, 1925 –
Sep 30, 1925
|
|
| 9
|
Robert M. La Follette Jr.
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Republican
|
Sep 30, 1925 –
Jan 3, 1947
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Elected to finish his father's term
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| 70th
|
15
|
Elected in 1926.Lost renomination.
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Mar 4, 1927 –
Mar 3, 1933
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Republican
|
John J. Blaine
|
12
|
| Re-elected in 1928.
|
15
|
71st
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| 72nd
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| 73rd
|
16
|
Elected in 1932.Lost re-election.
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Mar 4, 1933 –
Jan 3, 1939
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Democratic
|
F. Ryan Duffy
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13
|
| Progressive
|
Re-elected in 1934.
|
16
|
74th
|
| 75th
|
| 76th
|
17
|
Elected in 1938.
|
Jan 3, 1939 –
Jan 3, 1963
|
Republican
|
Alexander Wiley
|
14
|
| Re-elected in 1940.Lost nomination as a Republican.
|
17
|
77th
|
| 78th
|
| 79th
|
18
|
Re-elected in 1944.
|
| 10
|
Joseph McCarthy
|
Republican
|
Jan 3, 1947 –
May 2, 1957
|
Elected in 1946.
|
18
|
80th
|
| 81st
|
| 82nd
|
19
|
Re-elected in 1950.
|
| Re-elected in 1952.Died.
|
19
|
83rd
|
| 84th
|
| 85th
|
20
|
Re-elected in 1956.Lost re-election.
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| Vacant
|
May 2, 1957 –
Aug 27, 1957
|
|
| 11
|
William Proxmire
|
Democratic
|
Aug 28, 1957 –
Jan 3, 1989
|
Elected to finish McCarthy's term
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| Re-elected in 1958.
|
20
|
86th
|
| 87th
|
| 88th
|
21
|
Elected in 1962.
|
Jan 3, 1963 –
Jan 3, 1981
|
Democratic
|
Gaylord Nelson
|
15
|
| Re-elected in 1964.
|
21
|
89th
|
| 90th
|
| 91st
|
22
|
Re-elected in 1968.
|
| Re-elected in 1970.
|
22
|
92nd
|
| 93rd
|
| 94th
|
23
|
Re-elected in 1974.Lost re-election.
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| Re-elected in 1976.
|
23
|
95th
|
| 96th
|
| 97th
|
24
|
Elected in 1980.
|
Jan 3, 1981 –
Jan 3, 1993
|
Republican
|
Bob Kasten
|
16
|
| Re-elected in 1982.Retired.
|
24
|
98th
|
| 99th
|
| 100th
|
25
|
Re-elected in 1986.Lost re-election.
|
| 12
|
Herb Kohl
|
Democratic
|
Jan 3, 1989 –
Jan 3, 2013
|
Elected in 1988.
|
25
|
101st
|
| 102nd
|
| 103rd
|
26
|
Elected in 1992.
|
Jan 3, 1993 –
Jan 3, 2011
|
Democratic
|
Russ Feingold
|
17
|
| Re-elected in 1994.
|
26
|
104th
|
| 105th
|
| 106th
|
27
|
Re-elected in 1998.
|
| Re-elected in 2000.
|
27
|
107th
|
| 108th
|
| 109th
|
28
|
Re-elected in 2004.Lost re-election.
|
| Re-elected in 2006.Retired.
|
28
|
110th
|
| 111th
|
| 112th
|
29
|
Elected in 2010.
|
Jan 3, 2011 –
present
|
Republican
|
Ron Johnson
|
18
|
| 13
|
Tammy Baldwin
|
Democratic
|
Jan 3, 2013 –
present
|
Elected in 2012.
|
29
|
113th
|
| 114th
|
| 115th
|
30
|
Re-elected in 2016.
|
| Re-elected in 2018.
|
30
|
116th
|
| 117th
|
| 118th
|
31
|
Re-elected in 2022.
|
| To be determined in the 2024 election.
|
31
|
119th
|
| 120th
|
| 121st
|
32
|
To be determined in the 2028 election.
|
| #
|
Senator
|
Party
|
Years in office
|
Electoral history
|
T
|
C
|
T
|
Electoral history
|
Years in office
|
Party
|
Senator
|
#
|
| Class 1
|
Class 3
|
