O'Fallon, IL politics & representatives
O'Fallon is represented in Congress by Senators Richard J. Durbin and Tammy Duckworth and Representatives Mike Bost and Nikki Budzinski. J. B. Pritzker is governor.
Who represents O'Fallon in Washington and in Illinois, with how to reach each office.
How O'Fallon voted in 2024
Official results for O'Fallon's own voters.
President 14,840 votes
St. Clair County: Harris 52.5%, Trump 44.7% · Illinois: Harris 54.4%, Trump 43.5%
U.S. House · Illinois's 12th District 367,629 votes
Covers about 94% of O'Fallon · whole-district result
U.S. House · Illinois's 13th District 330,119 votes
Covers about 6% of O'Fallon · whole-district result
Source: MIT Election Data + Science Lab, official 2024 precinct returns (statewide totals from its official state files). Percentages are of votes for candidates; blank and spoiled ballots aren't counted.
Who represents O'Fallon in Congress
U.S. Senate Both senators represent all of Illinois
U.S. House · Illinois's 12th District Covers about 94% of O'Fallon
U.S. House · Illinois's 13th District Covers about 6% of O'Fallon
O'Fallon is split between 2 congressional districts. Find yours by ZIP code ↗
Who represents O'Fallon in state government
State Senate · District 55 Covers about 59% of O'Fallon
State Senate · District 57 Covers about 41% of O'Fallon
State House · District 109 Covers about 59% of O'Fallon
State House · District 114 Covers about 32% of O'Fallon
State House · District 113 Covers about 9% of O'Fallon
O'Fallon is split between state legislative districts. Find yours by address ↗
O'Fallon's own government: Town Hall →
Sources: congressional and state legislative districts from the U.S. Census Bureau (119th Congress, 2024 state districts); members of Congress from the congress-legislators project (portraits public domain); governors and state legislators from Open States. Districts are matched to O'Fallon by land area, so if the town is split, your street decides which one is yours.