| State: | Illinois |
| District Number: | 12 |
| Image Caption: | Interactive map of district boundaries since January 3, 2023 |
| Representative: | Mike Bost |
| Party: | Republican |
| Residence: | Murphysboro |
| English Area: | 14296.2 |
| Percent Urban: | 75.4 |
| Percent Rural: | 24.6 |
| Population: | 749,426 |
| Population Year: | 2023 |
| Median Income: | $65,076[1] |
| Percent White: | 86.9 |
| Percent Hispanic: | 2.8 |
| Percent Black: | 4.9 |
| Percent Asian: | 1.0 |
| Percent More Than One Race: | 3.9 |
| Percent Other Race: | 0.5 |
| Cpvi: | R+24[2] |
The 12th congressional district of Illinois is a congressional district in the southern part of U.S. state of Illinois. It has been represented by Republican Mike Bost since 2015. With a Cook Partisan Voting Index of R+24, it is the most Republican district in Illinois.[2]
The district covers parts of Madison and St. Clair counties, and all of Alexander, Franklin, Hamilton, Jackson, Jefferson, Monroe, Perry, Pulaski, Randolph, Union and Williamson counties, as of the 2011 redistricting which followed the 2010 census. All or parts of Belleville, Cahokia, Carbondale, Collinsville, East St. Louis, Granite City, Herrin, Marion, Mt. Vernon, O'Fallon, Shiloh and Swansea are included.[3] The representatives for these districts were elected in the 2012 primary and general elections, and the boundaries became effective on January 5, 2013.
| County | Seat | Population | ||
|---|---|---|---|---|
| 23 | Clark | Marshall | 15,088 | |
| 25 | Clay | Louisville | 12,999 | |
| 27 | Clinton | Carlyle | 36,785 | |
| 29 | Coles | Charleston | 46,060 | |
| 33 | Crawford | Robinson | 18,300 | |
| 35 | Cumberland | Toledo | 10,261 | |
| 47 | Edwards | Albion | 5,968 | |
| 49 | Effingham | Effingham | 34,331 | |
| 59 | Gallatin | Shawneetown | 4,670 | |
| 65 | Hamilton | McLeansboro | 7,911 | |
| 69 | Hardin | Elizabethtown | 3,569 | |
| 77 | Jackson | Murphysboro | 52,141 | |
| 79 | Jasper | Newton | 9,144 | |
| 81 | Jefferson | Mount Vernon | 36,320 | |
| 87 | Johnson | Vienna | 13,326 | |
| 101 | Lawrence | Lawrenceville | 14,813 | |
| 121 | Marion | Salem | 36,673 | |
| 125 | Massac | Metropolis | 13,661 | |
| 133 | Monroe | Waterloo | 34,957 | |
| 145 | Perry | Pinckneyville | 20,503 | |
| 151 | Pope | Golconda | 3,707 | |
| 153 | Pulaski | Mound City | 4,911 | |
| 157 | Randolph | Chester | 29,815 | |
| 165 | Saline | Harrisburg | 22,873 | |
| 163 | St. Clair | Belleville | 251,018 | |
| 181 | Union | Jonesboro | 16,667 | |
| 185 | Wabash | Mount Carmel | 10,942 | |
| 191 | Wayne | Fairfield | 15,761 | |
| 193 | White | Carmi | 13,401 | |
| 199 | Williamson | Marion | 66,706 |
Following the 2020 redistricting, this district will go from covering southeastern Illinois to encompassing the entirety of Southern Illinois, spanning the Illinois-Missouri-Kentucky-Indiana border. It will take in Monroe, Randolph, Clinton, Perry, Jackson, Union, Alexander, Pulaski, Massac, Johnson, Williamson, Jefferson, Marion, Clay, Effingham, Wayne, Hamilton, Saline, Pope, Hardin, Gallatin, White, Edwards, Wabash, Richland, Lawrence, Jasper, Crawford, Cumberland, and Clark Counties, most of St. Clair County, and half of Coles County.
St. Clair County is split between this district and the 13th district. They are partitioned by a Conrail line, Tanglewood Parkway, Donner Ridge, Hollywood Heights Rd, Oliver St, CSX Transportation Line, S Oak St, W 5th St, S Lincoln Ave, E US Highway 50, County Rd 218, Old O'Fallon Rd, Frank Scott Parkway E, N Green Mount Rd, S Green Mount Rd, Park Rd, S 59th St, Old St. Louis Rd, Illinois Highway 15, Rolling Acres Ln, Excellence Dr, Powdermill Creek, Cemetery Rd, and Illinois Highway 50. The 12th district takes in the municipalities of Mascoutah, Lebanon, New Athens, Marissa, Millstadt, Smithton, Freeburg, Summerfield, Scott AFB, Rentchler, Floraville, Paderborn, Fayetteville, St. Libory, Darmstadt, and Lenzburg; most of Shiloh; half of O'Fallon; and part of Caseyville, Fairview Heights, and Belleville.
Coles County is split between this district and the 15th district. They are partitioned by West St, North County Rd 1800 East, Lincoln Prairie Grass Trail, 18th St, County Rd 1600 East, County Rd 400 North, County Rd 1240 East, Illinois Route 16, Dettro Dr, 700 North Rd, Old Fellow Rd, and the Kickapoo Creek. The 12th district takes in the communities of Ashmore, Oakland, Lerna, Janesville (shared with Cumberland County), and Trilla; part of southern Mattoon; and part of Charleston.
This table indicates how the district has voted in U.S. presidential elections; election results reflect voting in the district as it was configured at the time of the election, not as it is configured today.
| Year | Office | Results | |
|---|---|---|---|
| 2000 | President | Al Gore 53% – George W. Bush 44% | |
| 2004 | President | John Kerry 52% – George W. Bush 48% | |
| 2008 | President | Barack Obama 55% – John McCain 44% | |
| 2012 | President | Barack Obama 50% – Mitt Romney 48% | |
| 2016 | President | Donald Trump 55% – Hillary Clinton 40% | |
| 2020 | President | Donald Trump 56% – Joe Biden 41% |
This table indicates how the district has voted in recent statewide elections; election results reflect voting in the district as it is currently configured, not necessarily as it was at the time of these elections.
| Year | Office | Results |
|---|---|---|
| 2016 | President | Donald Trump 68.5% – Hillary Clinton 26.0% |
| Senate | Mark Kirk 55.9% – Tammy Duckworth 39.2% | |
| 2018 | Governor | Bruce Rauner 57.0% – J. B. Pritzker 33.4% |
| Attorney General | Erika Harold 66.7% – Kwame Raoul 30.2% | |
| Secretary of State | Jason Helland 50.8% – Jesse White 47.1% | |
| 2020 | President | Donald Trump 70.5% – Joe Biden 27.7% |
| Senate | Mark Curran 66.5% – Dick Durbin 30.9% | |
| 2022 | Senate | Kathy Salvi 67.9% – Tammy Duckworth 30.3% |
| Governor | Darren Bailey 72.4% – J. B. Pritzker 25.2% | |
| Attorney General | Tom Devore 72.0% – Kwame Raoul 25.6% | |
| Secretary of State | Dan Brady 72.0% – Alexi Giannoulias 25.8% |
| Name | Party | Years | Cong– ress | Electoral history | Counties | |||
|---|---|---|---|---|---|---|---|---|
| District created March 4, 1863 | ||||||||
| align=left | William Ralls Morrison | Democratic | nowrap | March 4, 1863 – March 3, 1865 | Elected in 1862. Lost re-election. | 1863–1873 Clinton, Madison, Monroe, Randolph, St. Clair, and Washington | ||
| align=left | Jehu Baker | Republican | nowrap | March 4, 1865 – March 3, 1869 | Elected in 1864. Re-elected in 1866. Retired. | |||
| align=left | John B. Hay | Republican | nowrap | March 4, 1869 – March 3, 1873 | Elected in 1868. Re-elected in 1870. Redistricted to the and lost re-election. | |||
| align=left | James Carroll Robinson | Democratic | nowrap | March 4, 1873 – March 3, 1875 | Redistricted from the and re-elected in 1872. Retired. | 1873–1883 Cass, Christian, Menard, Morgan, Sangamon, and Scott | ||
| align=left | William McKendree Springer | Democratic | nowrap | March 4, 1875 – March 3, 1883 | Elected in 1874. Re-elected in 1876. Re-elected in 1878. Re-elected in 1880. Redistricted to the . | |||
| align=left | James M. Riggs | Democratic | nowrap | March 4, 1883 – March 3, 1887 | Elected in 1882. Re-elected in 1884. Retired. | 1883–1895 | ||
| align=left | George A. Anderson | Democratic | nowrap | March 4, 1887 – March 3, 1889 | Elected in 1886. Retired. | |||
| align=left | Scott Wike | Democratic | nowrap | March 4, 1889 – March 3, 1893 | Elected in 1888. Re-elected in 1890. Lost renomination. | |||
| align=left | John James McDannold | Democratic | nowrap | March 4, 1893– March 3, 1895 | Elected in 1892. Retired. | |||
| align=left | Joseph Gurney Cannon | Republican | nowrap | March 4, 1895– March 3, 1903 | Redistricted from the and re-elected in 1894. Re-elected in 1896. Re-elected in 1898. Re-elected in 1900. Redistricted to the . | 1895–1903 Iroquois, Kankakee, Vermillion, and Will | ||
| align=left | Charles Eugene Fuller | Republican | nowrap | March 4, 1903– March 3, 1913 | Elected in 1902. Re-elected in 1904. Re-elected in 1906. Re-elected in 1908. Re-elected in 1910. Lost re-election. | 1903–1913 Boone, DeKalb, Grundy, Kendall, LaSalle, and Winnebago | ||
| align=left | William H. Hinebaugh | Progressive | nowrap | March 4, 1913– March 3, 1915 | Elected in 1912. Lost re-election. | 1913–1949 Boone, DeKalb, Grundy, Kendall, LaSalle, and Winnebago | ||
| align=left | Charles Eugene Fuller | Republican | nowrap | March 4, 1915– June 25, 1926 | Elected again in 1914. Re-elected in 1916. Re-elected in 1918. Re-elected in 1920. Re-elected in 1922. Re-elected in 1924. Died. | |||
| Vacant | nowrap | June 25, 1926– March 3, 1927 | ||||||
| align=left | John T. Buckbee | Republican | nowrap | March 4, 1927– April 23, 1936 | Elected in 1926. Re-elected in 1928. Re-elected in 1930. Re-elected in 1932. Re-elected in 1934. Died. | |||
| Vacant | nowrap | April 23, 1936– January 3, 1937 | ||||||
| align=left | Noah M. Mason | Republican | nowrap | January 3, 1937– January 3, 1949 | Elected in 1936. Re-elected in 1938. Re-elected in 1940. Re-elected in 1942. Re-elected in 1944. Re-elected in 1946. Redistricted to the . | |||
Edgar A. Jonas | Republican | January 3, 1949– January 3, 1955 | Elected in 1948. Re-elected in 1950. Re-elected in 1952. Lost re-election. | 1949–1953 Cook | ||||
| 1953–1963 Cook | ||||||||
| align=left | Charles A. Boyle | Democratic | nowrap | January 3, 1955– November 4, 1959 | Elected in 1954. Re-elected in 1956. Re-elected in 1958. Died. | |||
| Vacant | nowrap | November 4, 1959– January 3, 1961 | ||||||
| align=left | Edward Rowan Finnegan | Democratic | nowrap | January 3, 1961– January 3, 1963 | Elected in 1960. Redistricted to the . | |||
Robert McClory | Republican | January 3, 1963– January 3, 1973 | Elected in 1962. Re-elected in 1964. Re-elected in 1966. Re-elected in 1968. Re-elected in 1970. Redistricted to the . | 1963–1967 Boone, Lake, and McHenry | ||||
| 1967–1973 Cook, Lake, and McHenry | ||||||||
Phil Crane | Republican | January 3, 1973– January 3, 1993 | Elected in 1972. Re-elected in 1974. Re-elected in 1976. Re-elected in 1978. Re-elected in 1980. Re-elected in 1982. Re-elected in 1984. Re-elected in 1986. Re-elected in 1988. Re-elected in 1990. Redistricted to the . | 1973–1983 Cook and Lake | ||||
| 1983–1993 Cook, Lake, and McHenry | ||||||||
Jerry Costello | Democratic | January 3, 1993– January 3, 2013 | Redistricted from the and re-elected in 1992. Re-elected in 1994. Re-elected in 1996. Re-elected in 1998. Re-elected in 2000. Re-elected in 2002. Re-elected in 2004. Re-elected in 2006. Re-elected in 2008. Re-elected in 2010. Retired. | 1993–2003 Alexander, Jackson, Madison, Monroe, Perry, Randolph, St. Clair, Union, and Williamson | ||||
| 2003–2013 Alexander, Franklin, Jackson, Madison, Monroe, Perry, Pulaski, Randolph, St. Clair, Union, Williamson | ||||||||
| align=left | William Enyart | Democratic | nowrap | January 3, 2013– January 3, 2015 | Elected in 2012. Lost re-election. | 2013–2023 Alexander, Franklin, Jackson, Jefferson, Madison, Monroe, Perry, Pulaski, Randolph, St. Clair, Union, and Williamson | ||
Mike Bost | Republican | January 3, 2015– present | Elected in 2014. Re-elected in 2016. Re-elected in 2018. Re-elected in 2020. Re-elected in 2022. Re-elected in 2024. | |||||
| 2023–present Alexander, Clark, Clay, Clinton, Coles (part), Crawford, Cumberland, Edwards, Effingham, Franklin, Gallatin, Hamilton, Hardin, Jackson, Jasper, Jefferson, Johnson, Lawrence, Marion, Massac, Monroe, Perry, Pope, Pulaski, Randolph, Richland, Saline, St. Clair (part), Union, Wabash, Washington, Wayne, White, and Williamson | ||||||||
See main article: United States House of Representatives elections in Illinois, 2012.