# Illinois's 12th congressional district

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.

## History
### 2011 redistricting

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. The representatives for these districts were elected in the 2012 primary and general elections, and the boundaries became effective on January 5, 2013.

## Composition

Composition :
| # | 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 |

### Cities and CDPs with 10,000 or more people

* Belleville – 42,404
* O'Fallon – 32,289
* Carbondale – 25,083
* Charleston – 17,286
* Mattoon – 16,870
* Marion – 16,855
* Fairview Heights – 16,706
* Mount Vernon – 14,600
* Shiloh – 14,098
* Herrin – 12,352
* Effingham – 12,252
* Centralia – 12,182
* Waterloo – 11,013
* Columbia – 10,999

### 2,500 to 10,000 people

* Mascoutah – 8,754
* Olney – 8,701
* Harrisburg – 8,219
* Chester – 7,640
* Salem – 7,282
* West Frankfort – 7,275
* Robinson – 7,150
* Murphysboro – 7,093
* Mount Carmel – 7,015
* Benton – 6,709
* Metropolis – 5,969
* Carterville – 5,848
* Du Quoin – 5,827
* Pinckneyville – 5,066
* Fairfield – 4,883
* Carmi – 4,865
* Flora – 4,803
* Lebanon – 4,691
* Breese – 4,641
* Freeburg – 4,582
* Caseyville – 4,400
* Anna – 4,303
* Lawrenceville – 4,164
* Sparta – 4,095
* Millstadt – 4,071
* Smithton – 4,006
* Marshall – 3,947
* Red Bud – 3,804
* Eldorado – 3,743
* Scott AFB – 3,612
* New Baden – 3,428
* Johnston City – 3,384
* Carlyle – 3,253
* Nashville – 3,105
* Newton – 2,777
* Christopher – 2,697
* Trenton – 2,690
* McLeansboro – 2,675
* Sumner – 2,631
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.

## Recent election results from statewide races

| Year | Office | Results |
| 2008 | President | McCain 54% - 44% |
| 2012 | President | Romney 63% - 37% |
| 2016 | President | Trump 69% - 26% |
| 2016 | Senate | Kirk 56% - 39% |
| 2016 | Comptroller (Spec.) | Munger 63% - 32% |
| 2018 | Governor | Rauner 57% - 33% |
| 2018 | Attorney General | Harold 67% - 30% |
| 2018 | Secretary of State | Helland 51% - 47% |
| 2018 | Comptroller | Senger 61% - 36% |
| 2018 | Treasurer | Dodge 63% - 34% |
| 2020 | President | Trump 70% - 28% |
| 2020 | Senate | Curran 66% - 31% |
| 2022 | Senate | Salvi 68% - 30% |
| 2022 | Governor | Bailey 73% - 25% |
| 2022 | Attorney General | DeVore 72% - 25% |
| 2022 | Secretary of State | Brady 72% - 25% |
| 2022 | Comptroller | Teresi 68% - 30% |
| 2022 | Treasurer | Demmer 72% - 26% |
| 2024 | President | Trump 71% - 28% |

## List of members representing the district

| Name | Party | Years | Cong– ress | Electoral history | Counties |
| District created March 4, 1863 ||||||
| William Ralls Morrison (Waterloo) | Democratic | March 4, 1863 – March 3, 1865 | 38th | Elected in 1862. Lost re-election. | 1863–1873 Clinton, Madison, Monroe, Randolph, St. Clair, and Washington |
| Jehu Baker (Belleville) | Republican | March 4, 1865 – March 3, 1869 | 39th 40th | Elected in 1864. Re-elected in 1866. Retired. | 1863–1873 Clinton, Madison, Monroe, Randolph, St. Clair, and Washington |
| John B. Hay (Belleville) | Republican | March 4, 1869 – March 3, 1873 | 41st 42nd | Elected in 1868. Re-elected in 1870. Redistricted to the 17th district and lost re-election. | 1863–1873 Clinton, Madison, Monroe, Randolph, St. Clair, and Washington |
| James Carroll Robinson (Springfield) | Democratic | March 4, 1873 – March 3, 1875 | 43rd | Redistricted from the 8th district and re-elected in 1872. Retired. | 1873–1883 Cass, Christian, Menard, Morgan, Sangamon, and Scott |
| William McKendree Springer (Springfield) | Democratic | March 4, 1875 – March 3, 1883 | 44th 45th 46th 47th | Elected in 1874. Re-elected in 1876. Re-elected in 1878. Re-elected in 1880. Redistricted to the 13th district. | 1873–1883 Cass, Christian, Menard, Morgan, Sangamon, and Scott |
| James M. Riggs (Winchester) | Democratic | March 4, 1883 – March 3, 1887 | 48th 49th | Elected in 1882. Re-elected in 1884. Retired. | 1883–1895 [data missing] |
| George A. Anderson (Quincy) | Democratic | March 4, 1887 – March 3, 1889 | 50th | Elected in 1886. Retired. | 1883–1895 [data missing] |
| Scott Wike (Pittsfield) | Democratic | March 4, 1889 – March 3, 1893 | 51st 52nd | Elected in 1888. Re-elected in 1890. Lost renomination. | 1883–1895 [data missing] |
| John James McDannold (Mount Sterling) | Democratic | March 4, 1893– March 3, 1895 | 53rd | Elected in 1892. Retired. | 1883–1895 [data missing] |
| Joseph Gurney Cannon (Danville) | Republican | March 4, 1895– March 3, 1903 | 54th 55th 56th 57th | Redistricted from the 15th district and re-elected in 1894. Re-elected in 1896. Re-elected in 1898. Re-elected in 1900. Redistricted to the 18th district. | 1895–1903 Iroquois, Kankakee, Vermillion, and Will |
| Charles Eugene Fuller (Belvidere) | Republican | March 4, 1903– March 3, 1913 | 58th 59th 60th 61st 62nd | 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 |
| William H. Hinebaugh (Ottawa) | Progressive | March 4, 1913– March 3, 1915 | 63rd | Elected in 1912. Lost re-election. | 1913–1949 Boone, DeKalb, Grundy, Kendall, LaSalle, and Winnebago |
| Charles Eugene Fuller (Belvidere) | Republican | March 4, 1915– June 25, 1926 | 64th 65th 66th 67th 68th 69th | 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. | 1913–1949 Boone, DeKalb, Grundy, Kendall, LaSalle, and Winnebago |
| Vacant | Vacant | June 25, 1926– March 3, 1927 | 69th | | 1913–1949 Boone, DeKalb, Grundy, Kendall, LaSalle, and Winnebago |
| John T. Buckbee (Rockford) | Republican | March 4, 1927– April 23, 1936 | 70th 71st 72nd 73rd 74th | Elected in 1926. Re-elected in 1928. Re-elected in 1930. Re-elected in 1932. Re-elected in 1934. Died. | 1913–1949 Boone, DeKalb, Grundy, Kendall, LaSalle, and Winnebago |
| Vacant | Vacant | April 23, 1936– January 3, 1937 | 74th | | 1913–1949 Boone, DeKalb, Grundy, Kendall, LaSalle, and Winnebago |
| Noah M. Mason (Oglesby) | Republican | January 3, 1937– January 3, 1949 | 75th 76th 77th 78th 79th 80th | 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 15th district. | 1913–1949 Boone, DeKalb, Grundy, Kendall, LaSalle, and Winnebago |
| Edgar A. Jonas (Chicago) | Republican | January 3, 1949– January 3, 1955 | 81st 82nd 83rd | Elected in 1948. Re-elected in 1950. Re-elected in 1952. Lost re-election. | 1949–1953 Cook |
| Edgar A. Jonas (Chicago) | Republican | January 3, 1949– January 3, 1955 | 81st 82nd 83rd | Elected in 1948. Re-elected in 1950. Re-elected in 1952. Lost re-election. | 1953–1963 Cook |
| Charles A. Boyle (Chicago) | Democratic | January 3, 1955– November 4, 1959 | 84th 85th 86th | Elected in 1954. Re-elected in 1956. Re-elected in 1958. Died. | 1953–1963 Cook |
| Vacant | Vacant | November 4, 1959– January 3, 1961 | 86th | | 1953–1963 Cook |
| Edward Rowan Finnegan (Chicago) | Democratic | January 3, 1961– January 3, 1963 | 87th | Elected in 1960. Redistricted to the 9th district. | 1953–1963 Cook |
| Robert McClory (Lake Bluff) | Republican | January 3, 1963– January 3, 1973 | 88th 89th 90th 91st 92nd | Elected in 1962. Re-elected in 1964. Re-elected in 1966. Re-elected in 1968. Re-elected in 1970. Redistricted to the 13th district. | 1963–1967 Boone, Lake, and McHenry |
| Robert McClory (Lake Bluff) | Republican | January 3, 1963– January 3, 1973 | 88th 89th 90th 91st 92nd | Elected in 1962. Re-elected in 1964. Re-elected in 1966. Re-elected in 1968. Re-elected in 1970. Redistricted to the 13th district. | 1967–1973 Cook, Lake, and McHenry |
| Phil Crane (McHenry) | Republican | January 3, 1973– January 3, 1993 | 93rd 94th 95th 96th 97th 98th 99th 100th 101st 102nd | 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 8th district. | 1973–1983 Cook and Lake |
| Phil Crane (McHenry) | Republican | January 3, 1973– January 3, 1993 | 93rd 94th 95th 96th 97th 98th 99th 100th 101st 102nd | 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 8th district. | 1983–1993 Cook, Lake, and McHenry |
| Jerry Costello (Belleville) | Democratic | January 3, 1993– January 3, 2013 | 103rd 104th 105th 106th 107th 108th 109th 110th 111th 112th | Redistricted from the 21st district 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 |
| Jerry Costello (Belleville) | Democratic | January 3, 1993– January 3, 2013 | 103rd 104th 105th 106th 107th 108th 109th 110th 111th 112th | Redistricted from the 21st district 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. | 2003–2013 Alexander, Franklin, Jackson, Madison, Monroe, Perry, Pulaski, Randolph, St. Clair, Union, Williamson |
| William Enyart (Belleville) | Democratic | January 3, 2013– January 3, 2015 | 113th | Elected in 2012. Lost re-election. | 2013–2023 Alexander, Franklin, Jackson, Jefferson, Madison, Monroe, Perry, Pulaski, Randolph, St. Clair, Union, and Williamson |
| Mike Bost (Murphysboro) | Republican | January 3, 2015– present | 114th 115th 116th 117th 118th 119th | Elected in 2014. Re-elected in 2016. Re-elected in 2018. Re-elected in 2020. Re-elected in 2022. Re-elected in 2024. | 2013–2023 Alexander, Franklin, Jackson, Jefferson, Madison, Monroe, Perry, Pulaski, Randolph, St. Clair, Union, and Williamson |
| Mike Bost (Murphysboro) | Republican | January 3, 2015– present | 114th 115th 116th 117th 118th 119th | 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 |

## Elections
### 2012

Illinois's 12th congressional district election results, 2012 :
| Party | Party | Candidate | Votes | % |
| | Democratic | William Enyart | 157,000 | 51.7 |
| | Republican | Jason Plummer | 129,902 | 42.7 |
| | Green | Paula Bradshaw | 17,045 | 5.6 |
| | Write-in | Shon-Tiyon Horton | 2 | 0.0 |
| Total votes | Total votes | Total votes | 303,947 | 100 |

### 2014

Illinois's 12th congressional district, 2014 :
| Party | Party | Candidate | Votes | % |
| | Republican | Mike Bost | 110,038 | 52.5 |
| | Democratic | William Enyart (incumbent) | 87,860 | 41.9 |
| | Green | Paula Bradshaw | 11,840 | 5.6 |
| Total votes | Total votes | Total votes | 209,738 | 100.0 |
| | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic | Republican gain from Democratic |

### 2016

Illinois's 12th congressional district, 2016 :
| Party | Party | Candidate | Votes | % |
| | Republican | Mike Bost (incumbent) | 169,976 | 54.3 |
| | Democratic | C.J. Baricevic | 124,246 | 39.7 |
| | Green | Paula Bradshaw | 18,780 | 6.0 |
| Total votes | Total votes | Total votes | 313,002 | 100.0 |
| | Republican hold | Republican hold | Republican hold | Republican hold |

### 2018

Illinois's 12th congressional district, 2018 :
| Party | Party | Candidate | Votes | % |
| | Republican | Mike Bost (incumbent) | 134,884 | 51.6 |
| | Democratic | Brendan Kelly | 118,724 | 45.4 |
| | Green | Randall Auxier | 7,935 | 3.0 |
| Total votes | Total votes | Total votes | 261,543 | 100.0 |
| | Republican hold | Republican hold | Republican hold | Republican hold |

### 2020

Illinois's 12th congressional district, 2020 :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Mike Bost (incumbent) | 194,839 | 60.43 | +8.86% |
| | Democratic | Raymond Lenzi | 127,577 | 39.57 | −5.82% |
| Total votes | Total votes | Total votes | 322,416 | 100.0 | |
| | Republican hold | Republican hold | Republican hold | Republican hold | Republican hold |

### 2022

Illinois's 12th congressional district, 2022 :
| Party | Party | Candidate | Votes | % |
| | Republican | Mike Bost (incumbent) | 218,379 | 75.00 |
| | Democratic | Chip Markel | 72,791 | 25.00 |
| | Write-in | Write-in | 1 | 0.00 |
| Total votes | Total votes | Total votes | 291,171 | 100.0 |
| | Republican hold | Republican hold | Republican hold | Republican hold |

### 2024

Illinois's 12th congressional district, 2024 :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Mike Bost (incumbent) | 272,754 | 74.19 | −0.81% |
| | Democratic | Brian Roberts | 94,875 | 25.81 | +0.81% |
| Total votes | Total votes | Total votes | 367,629 | 100.0 | |
| | Republican hold | Republican hold | Republican hold | Republican hold | Republican hold |