# Wisconsin's 15th Senate district

The 15th Senate district of Wisconsin is one of 33 districts in the Wisconsin Senate. Located in southern Wisconsin, the district comprises most of Rock County and parts of northwest Walworth County and southern Jefferson County. It includes the cities of Janesville, Beloit, Edgerton, Evansville, Milton, and Whitewater.

## Current elected officials

Mark Spreitzer is the senator representing the 15th district since January 2023. He previously served in the State Assembly, representing the 45th Assembly district from 2015 to 2023.
Each Wisconsin State Senate district is composed of three Wisconsin State Assembly districts. The 15th Senate district comprises the 43rd, 44th, and 45th Assembly districts. The current representatives of those districts are:
* Assembly District 43: Brienne Brown (D–Whitewater)
* Assembly District 44: Ann Roe (D–Janesville)
* Assembly District 45: Clinton Anderson (D–Beloit)
The 15th Senate district, in its current borders, crosses three different congressional districts. The portion of the district in Jefferson County falls within Wisconsin's 5th congressional district, which is represented by U.S. Representative Scott L. Fitzgerald; the portion in Walworth County and the cities of Janesville and Milton and the eastern part of Rock County fall within Wisconsin's 1st congressional district, which is represented by U.S. Representative Bryan Steil; the remainder of the district, in the western half of Rock county, falls within Wisconsin's 2nd congressional district, which is represented by U.S. Representative Mark Pocan.
* Main Street in downtown Whitewater
* Fulton Street Historic District in Edgerton
* Lappin-Hayes Block in downtown Janesville
* Historic Janesville Armory
* Courthouse Hill Historic District
* Downtown Beloit
* Middle College, part of Beloit College

## Past senators

The district has previously been represented by:
Note: the boundaries of districts have changed repeatedly over history. Previous politicians of a specific numbered district have represented a completely different geographic area, due to redistricting.
| Senator | Party | Notes | Session | Years | District Definition |
| District created | District created | District created | District created | 1848 | Rock County |
| Otis Norton | Whig | | 1st | 1848 | Rock County |
| Otis Norton | Whig | | 2nd | 1849 | Rock County |
| Otis Norton | Whig | | 3rd | 1850 | Rock County |
| Andrew Palmer | Dem. | | 4th | 1851 | Rock County |
| Andrew Palmer | Dem. | | 5th | 1852 | Rock County |
| Levi Sterling | Whig | | 6th | 1853 | 1852–1855 1856–1860 Iowa & Richland counties |
| Levi Sterling | Whig | | 7th | 1854 | 1852–1855 1856–1860 Iowa & Richland counties |
| Amasa Cobb | Rep. | | 8th | 1855 | 1852–1855 1856–1860 Iowa & Richland counties |
| Amasa Cobb | Rep. | | 9th | 1856 | 1852–1855 1856–1860 Iowa & Richland counties |
| Lemuel W. Joiner | Rep. | | 10th | 1857 | 1852–1855 1856–1860 Iowa & Richland counties |
| Lemuel W. Joiner | Rep. | | 11th | 1858 | 1852–1855 1856–1860 Iowa & Richland counties |
| Charles Rodolf | Dem. | | 12th | 1859 | 1852–1855 1856–1860 Iowa & Richland counties |
| Charles Rodolf | Dem. | | 13th | 1860 | 1852–1855 1856–1860 Iowa & Richland counties |
| Lemuel W. Joiner | Rep. | | 14th | 1861 | 1852–1855 1856–1860 Iowa & Richland counties |
| Lemuel W. Joiner | Rep. | | 15th | 1862 | 1861–1865 1866–1870 Iowa County |
| George L. Frost | Dem. | | 16th | 1863 | 1861–1865 1866–1870 Iowa County |
| George L. Frost | Dem. | | 17th | 1864 | 1861–1865 1866–1870 Iowa County |
| Wyman Lincoln | Natl. Union | | 18th | 1865 | 1861–1865 1866–1870 Iowa County |
| Wyman Lincoln | Natl. Union | | 19th | 1866 | 1861–1865 1866–1870 Iowa County |
| Joel Whitman | Natl. Union | | 20th | 1867 | 1861–1865 1866–1870 Iowa County |
| Joel Whitman | Rep. | | 21st | 1868 | 1861–1865 1866–1870 Iowa County |
| Lemuel W. Joiner | Rep. | | 22nd | 1869 | 1861–1865 1866–1870 Iowa County |
| Lemuel W. Joiner | Rep. | | 23rd | 1870 | 1861–1865 1866–1870 Iowa County |
| Francis Little | Rep. | Redistricted to 9th district | 24th | 1871 | 1861–1865 1866–1870 Iowa County |
| Carl H. Schmidt | Dem. | Redistricted from 19th district | 25th | 1872 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| Carl H. Schmidt | Dem. | Redistricted from 19th district | 26th | 1873 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| Carl H. Schmidt | Dem. | Redistricted from 19th district | 27th | 1874 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| John Schuette | Rep. | | 28th | 1875 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| John Schuette | Rep. | | 29th | 1876 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| Joseph Rankin | Dem. | | 30th | 1877 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| Joseph Rankin | Dem. | | 31st | 1878 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| Joseph Rankin | Dem. | | 32nd | 1879 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| Joseph Rankin | Dem. | | 33rd | 1880 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| Joseph Rankin | Dem. | | 34th | 1881 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| Joseph Rankin | Dem. | | 35th | 1882 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| John Carey | Dem. | | 36th | 1883–1884 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| John Carey | Dem. | | 37th | 1885–1886 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| John Carey | Dem. | | 38th | 1887–1888 | 1871–1875 1876–1881 1882–1887 Manitowoc County |
| William F. Nash | Dem. | Won 1888 special election. | 39th | 1889–1890 | Kewaunee & Manitowoc counties |
| William F. Nash | Dem. | Won 1888 special election. | 40th | 1891–1892 | Kewaunee & Manitowoc counties |
| William F. Nash | Dem. | Won 1888 special election. | 41st | 1893–1894 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| John McMullen | Dem. | | 42nd | 1895–1896 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| John McMullen | Dem. | | 43rd | 1897–1898 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Norman Knudson | Rep. | | 44th | 1899–1900 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Norman Knudson | Rep. | | 45th | 1901–1902 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Samuel W. Randolph | Dem. | | 46th | 1903–1904 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Samuel W. Randolph | Dem. | | 47th | 1905–1906 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Samuel W. Randolph | Dem. | | 48th | 1907–1908 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Samuel W. Randolph | Dem. | | 49th | 1909–1910 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Samuel W. Randolph | Dem. | | 50th | 1911–1912 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Samuel W. Randolph | Dem. | | 51st | 1913–1914 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Henry Rollman | Dem. | | 52nd | 1915–1916 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Henry Rollman | Dem. | | 53rd | 1917–1918 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Henry Kleist | Soc. | | 54th | 1919–1920 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Henry Kleist | Soc. | | 55th | 1921–1922 | 1892–1895 1896–1901 1902–1911 1912–1921 Calumet & Manitowoc counties |
| Alva Garey | Rep. | | 56th | 1923–1924 | 1922–1953 1954–1963 Rock County |
| Alva Garey | Rep. | | 57th | 1925–1926 | 1922–1953 1954–1963 Rock County |
| George W. Blanchard | Rep. | Resigned 1933 after election to U.S. House. | 58th | 1927–1928 | 1922–1953 1954–1963 Rock County |
| George W. Blanchard | Rep. | Resigned 1933 after election to U.S. House. | 59th | 1929–1930 | 1922–1953 1954–1963 Rock County |
| George W. Blanchard | Rep. | Resigned 1933 after election to U.S. House. | 60th | 1931–1932 | 1922–1953 1954–1963 Rock County |
| George W. Blanchard | Rep. | Resigned 1933 after election to U.S. House. | 61st | 1933–1934 | 1922–1953 1954–1963 Rock County |
| 1922–1953 1954–1963 Rock County |||
| Alexander Paul | Dem. | Won 1933 special election. | 61st | 1933–1934 | 1922–1953 1954–1963 Rock County |
| Maurice Coakley | Rep. | | 62nd | 1935–1936 | 1922–1953 1954–1963 Rock County |
| Maurice Coakley | Rep. | | 63rd | 1937–1938 | 1922–1953 1954–1963 Rock County |
| Maurice Coakley | Rep. | | 64th | 1939–1940 | 1922–1953 1954–1963 Rock County |
| Maurice Coakley | Rep. | | 65th | 1941–1942 | 1922–1953 1954–1963 Rock County |
| Robert P. Robinson | Rep. | | 66th | 1943–1944 | 1922–1953 1954–1963 Rock County |
| Robert P. Robinson | Rep. | | 67th | 1945–1946 | 1922–1953 1954–1963 Rock County |
| Robert P. Robinson | Rep. | | 68th | 1947–1948 | 1922–1953 1954–1963 Rock County |
| Robert P. Robinson | Rep. | | 69th | 1949–1950 | 1922–1953 1954–1963 Rock County |
| Robert P. Robinson | Rep. | | 70th | 1951–1952 | 1922–1953 1954–1963 Rock County |
| Robert P. Robinson | Rep. | | 71st | 1953–1954 | 1922–1953 1954–1963 Rock County |
| Peter P. Carr | Rep. | | 72nd | 1955–1956 | 1922–1953 1954–1963 Rock County |
| Peter P. Carr | Rep. | | 73rd | 1957–1958 | 1922–1953 1954–1963 Rock County |
| Peter P. Carr | Rep. | | 74th | 1959–1960 | 1922–1953 1954–1963 Rock County |
| Peter P. Carr | Rep. | | 75th | 1961–1962 | 1922–1953 1954–1963 Rock County |
| Peter P. Carr | Rep. | | 76th | 1963–1964 | 1922–1953 1954–1963 Rock County |
| Peter P. Carr | Rep. | | 77th | 1965–1966 | Walworth County & eastern Rock County Town of Bradford Town of Clinton Town of Harmony Town of Johnstown Town of La Prairie Town of Turtle Village of Clinton City of Beloit City of Janesville |
| George M. Borg | Rep. | Resigned Aug. 1967. | 78th | 1967–1968 | Walworth County & eastern Rock County Town of Bradford Town of Clinton Town of Harmony Town of Johnstown Town of La Prairie Town of Turtle Village of Clinton City of Beloit City of Janesville |
| Walworth County & eastern Rock County Town of Bradford Town of Clinton Town of Harmony Town of Johnstown Town of La Prairie Town of Turtle Village of Clinton City of Beloit City of Janesville |||
| James D. Swan | Rep. | Won 1967 special election. | 78th | 1967–1968 | Walworth County & eastern Rock County Town of Bradford Town of Clinton Town of Harmony Town of Johnstown Town of La Prairie Town of Turtle Village of Clinton City of Beloit City of Janesville |
| James D. Swan | Rep. | Won 1967 special election. | 79th | 1969–1970 | Walworth County & eastern Rock County Town of Bradford Town of Clinton Town of Harmony Town of Johnstown Town of La Prairie Town of Turtle Village of Clinton City of Beloit City of Janesville |
| James D. Swan | Rep. | Won 1967 special election. | 80th | 1971–1972 | Walworth County & eastern Rock County Town of Bradford Town of Clinton Town of Harmony Town of Johnstown Town of La Prairie Town of Turtle Village of Clinton City of Beloit City of Janesville |
| James D. Swan | Rep. | Won 1967 special election. | 81st | 1973–1974 | Western Racine County, eastern Rock County, & most of Walworth County Racine County Town of Burlington Town of Norway Town of Rochester Town of Waterford Village of Rochester Village of Waterford City of Burlington Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Lima Town of Rock Town of Turtle Village of Clinton City of Beloit Part of the city of Janesville Walworth County Town of Darien Town of Delavan Town of East Troy Town of Geneva Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Troy Town of Walworth Town of Whitewater Village of Darien Village of East Troy Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn City of Lake Geneva Part of the city of Whitewater |
| Timothy Cullen | Dem. | Resigned 1987 after appointed Secretary of Wisconsin Department of Health Services. | 82nd | 1975–1976 | Western Racine County, eastern Rock County, & most of Walworth County Racine County Town of Burlington Town of Norway Town of Rochester Town of Waterford Village of Rochester Village of Waterford City of Burlington Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Lima Town of Rock Town of Turtle Village of Clinton City of Beloit Part of the city of Janesville Walworth County Town of Darien Town of Delavan Town of East Troy Town of Geneva Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Troy Town of Walworth Town of Whitewater Village of Darien Village of East Troy Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn City of Lake Geneva Part of the city of Whitewater |
| Timothy Cullen | Dem. | Resigned 1987 after appointed Secretary of Wisconsin Department of Health Services. | 83rd | 1977–1978 | Western Racine County, eastern Rock County, & most of Walworth County Racine County Town of Burlington Town of Norway Town of Rochester Town of Waterford Village of Rochester Village of Waterford City of Burlington Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Lima Town of Rock Town of Turtle Village of Clinton City of Beloit Part of the city of Janesville Walworth County Town of Darien Town of Delavan Town of East Troy Town of Geneva Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Troy Town of Walworth Town of Whitewater Village of Darien Village of East Troy Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn City of Lake Geneva Part of the city of Whitewater |
| Timothy Cullen | Dem. | Resigned 1987 after appointed Secretary of Wisconsin Department of Health Services. | 84th | 1979–1980 | Western Racine County, eastern Rock County, & most of Walworth County Racine County Town of Burlington Town of Norway Town of Rochester Town of Waterford Village of Rochester Village of Waterford City of Burlington Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Lima Town of Rock Town of Turtle Village of Clinton City of Beloit Part of the city of Janesville Walworth County Town of Darien Town of Delavan Town of East Troy Town of Geneva Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Troy Town of Walworth Town of Whitewater Village of Darien Village of East Troy Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn City of Lake Geneva Part of the city of Whitewater |
| Timothy Cullen | Dem. | Resigned 1987 after appointed Secretary of Wisconsin Department of Health Services. | 85th | 1981–1982 | Western Racine County, eastern Rock County, & most of Walworth County Racine County Town of Burlington Town of Norway Town of Rochester Town of Waterford Village of Rochester Village of Waterford City of Burlington Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Lima Town of Rock Town of Turtle Village of Clinton City of Beloit Part of the city of Janesville Walworth County Town of Darien Town of Delavan Town of East Troy Town of Geneva Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Troy Town of Walworth Town of Whitewater Village of Darien Village of East Troy Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn City of Lake Geneva Part of the city of Whitewater |
| Timothy Cullen | Dem. | Resigned 1987 after appointed Secretary of Wisconsin Department of Health Services. | 86th | 1983–1984 | Most of Walworth County Southeast and central Rock County Town of Beloit Town of Bradford Town of Clinton Town of Janesville Town of La Prairie Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 1-13, 20, 21, City of Janesville |
| Timothy Cullen | Dem. | Resigned 1987 after appointed Secretary of Wisconsin Department of Health Services. | 87th | 1985–1986 | Most of Walworth County South and central Rock County Town of Beloit Town of Bradford Town of Clinton Town of Janesville Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 1, 3-14, 20, 21, City of Janesville |
| —Vacant-- | —Vacant-- | —Vacant-- | 88th | 1987–1988 | Most of Walworth County South and central Rock County Town of Beloit Town of Bradford Town of Clinton Town of Janesville Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 1, 3-14, 20, 21, City of Janesville |
| Timothy Weeden | Rep. | Won 1987 special election. | 88th | 1987–1988 | Most of Walworth County South and central Rock County Town of Beloit Town of Bradford Town of Clinton Town of Janesville Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 1, 3-14, 20, 21, City of Janesville |
| Timothy Weeden | Rep. | Won 1987 special election. | 89th | 1989–1990 | Most of Walworth County South and central Rock County Town of Beloit Town of Bradford Town of Clinton Town of Janesville Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 1, 3-14, 20, 21, City of Janesville |
| Timothy Weeden | Rep. | Won 1987 special election. | 90th | 1991–1992 | Most of Walworth County South and central Rock County Town of Beloit Town of Bradford Town of Clinton Town of Janesville Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 1, 3-14, 20, 21, City of Janesville |
| Timothy Weeden | Rep. | Won 1987 special election. | 91st | 1993–1994 | Most Walworth County Town of Darien Town of Delavan Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Walworth Village of Darien Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn Wards 1-6, 8, Town of Geneva South and east Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 2-4, Town of Harmony Wards 1-10, 13-22, City of Janesville |
| Timothy Weeden | Rep. | Won 1987 special election. | 92nd | 1995–1996 | Most Walworth County Town of Darien Town of Delavan Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Walworth Village of Darien Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn Wards 1-6, 8, Town of Geneva South and east Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 2-4, Town of Harmony Wards 1-10, 13-22, City of Janesville |
| Timothy Weeden | Rep. | Won 1987 special election. | 93rd | 1997–1998 | Most Walworth County Town of Darien Town of Delavan Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Walworth Village of Darien Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn Wards 1-6, 8, Town of Geneva South and east Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 2-4, Town of Harmony Wards 1-10, 13-22, City of Janesville |
| Judy Robson | Dem. | | 94th | 1999–2000 | Most Walworth County Town of Darien Town of Delavan Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Walworth Village of Darien Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn Wards 1-6, 8, Town of Geneva South and east Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 2-4, Town of Harmony Wards 1-10, 13-22, City of Janesville |
| Judy Robson | Dem. | | 95th | 2001–2002 | Most Walworth County Town of Darien Town of Delavan Town of La Grange Town of Lafayette Town of Linn Town of Lyons Town of Richmond Town of Sharon Town of Spring Prairie Town of Sugar Creek Town of Walworth Village of Darien Village of Fontana-on-Geneva Lake Village of Sharon Village of Walworth Village of Williams Bay City of Delavan City of Elkhorn Wards 1-6, 8, Town of Geneva South and east Rock County Town of Beloit Town of Bradford Town of Clinton Town of Johnstown Town of La Prairie Town of Newark Town of Rock Town of Turtle Village of Clinton City of Beloit Wards 2-4, Town of Harmony Wards 1-10, 13-22, City of Janesville |
| Judy Robson | Dem. | | 96th | 2003–2004 | Most of Rock County Town of Avon Town of Beloit Town of Bradford Town of Center Town of Clinton Town of Fulton Town of Harmony Town of Janesville Town of Johnstown Town of La Prairie Town of Milton Town of Newark Town of Plymouth Town of Porter Town of Rock Town of Spring Valley Town of Turtle Village of Clinton Village of Footville Village of Orfordville City of Beloit City of Edgerton City of Janesville City of Milton Part of Northwest Walworth County Town of Richmond Town of Whitewater City of Whitewater Part of Jefferson County City of Whitewater Part of Dane County City of Edgerton |
| Judy Robson | Dem. | | 97th | 2005–2006 | Most of Rock County Town of Avon Town of Beloit Town of Bradford Town of Center Town of Clinton Town of Fulton Town of Harmony Town of Janesville Town of Johnstown Town of La Prairie Town of Milton Town of Newark Town of Plymouth Town of Porter Town of Rock Town of Spring Valley Town of Turtle Village of Clinton Village of Footville Village of Orfordville City of Beloit City of Edgerton City of Janesville City of Milton Part of Northwest Walworth County Town of Richmond Town of Whitewater City of Whitewater Part of Jefferson County City of Whitewater Part of Dane County City of Edgerton |
| Judy Robson | Dem. | | 98th | 2007–2008 | Most of Rock County Town of Avon Town of Beloit Town of Bradford Town of Center Town of Clinton Town of Fulton Town of Harmony Town of Janesville Town of Johnstown Town of La Prairie Town of Milton Town of Newark Town of Plymouth Town of Porter Town of Rock Town of Spring Valley Town of Turtle Village of Clinton Village of Footville Village of Orfordville City of Beloit City of Edgerton City of Janesville City of Milton Part of Northwest Walworth County Town of Richmond Town of Whitewater City of Whitewater Part of Jefferson County City of Whitewater Part of Dane County City of Edgerton |
| Judy Robson | Dem. | | 99th | 2009–2010 | Most of Rock County Town of Avon Town of Beloit Town of Bradford Town of Center Town of Clinton Town of Fulton Town of Harmony Town of Janesville Town of Johnstown Town of La Prairie Town of Milton Town of Newark Town of Plymouth Town of Porter Town of Rock Town of Spring Valley Town of Turtle Village of Clinton Village of Footville Village of Orfordville City of Beloit City of Edgerton City of Janesville City of Milton Part of Northwest Walworth County Town of Richmond Town of Whitewater City of Whitewater Part of Jefferson County City of Whitewater Part of Dane County City of Edgerton |
| Timothy Cullen | Dem. | | 100th | 2011–2012 | Most of Rock County Town of Avon Town of Beloit Town of Bradford Town of Center Town of Clinton Town of Fulton Town of Harmony Town of Janesville Town of Johnstown Town of La Prairie Town of Milton Town of Newark Town of Plymouth Town of Porter Town of Rock Town of Spring Valley Town of Turtle Village of Clinton Village of Footville Village of Orfordville City of Beloit City of Edgerton City of Janesville City of Milton Part of Northwest Walworth County Town of Richmond Town of Whitewater City of Whitewater Part of Jefferson County City of Whitewater Part of Dane County City of Edgerton |
| Timothy Cullen | Dem. | | 101st | 2013–2014 | Most of Rock County Southeast Green County Southeast Dane County Southwest Jefferson County Town of Cold Spring Town of Sumner Part of the Town of Koshkonong City of Whitewater Part of northwest Walworth County Town of Whitewater City of Whitewater |
| Janis Ringhand | Dem. | | 102nd | 2015–2016 | Most of Rock County Southeast Green County Southeast Dane County Southwest Jefferson County Town of Cold Spring Town of Sumner Part of the Town of Koshkonong City of Whitewater Part of northwest Walworth County Town of Whitewater City of Whitewater |
| Janis Ringhand | Dem. | | 103rd | 2017–2018 | Most of Rock County Southeast Green County Southeast Dane County Southwest Jefferson County Town of Cold Spring Town of Sumner Part of the Town of Koshkonong City of Whitewater Part of northwest Walworth County Town of Whitewater City of Whitewater |
| Janis Ringhand | Dem. | | 104th | 2019–2020 | Most of Rock County Southeast Green County Southeast Dane County Southwest Jefferson County Town of Cold Spring Town of Sumner Part of the Town of Koshkonong City of Whitewater Part of northwest Walworth County Town of Whitewater City of Whitewater |
| Janis Ringhand | Dem. | | 105th | 2021–2022 | Most of Rock County Southeast Green County Southeast Dane County Southwest Jefferson County Town of Cold Spring Town of Sumner Part of the Town of Koshkonong City of Whitewater Part of northwest Walworth County Town of Whitewater City of Whitewater |
| Mark Spreitzer | Dem. | Elected 2022. | 106th | 2023–2024 | Southeast Dane County, parts of Green County, western Rock County |
| Mark Spreitzer | Dem. | Elected 2022. | 107th | 2025–2026 | |