Illinois's 12th congressional district: election results

U.S. House elections in Illinois's 12th congressional district, 1976 to 2024: winners, vote shares and margins. District lines are redrawn after each census, so the area covered changes over time.

Current representative: Mike Bost (Republican), term ends 2027-01-03.

Illinois's 12th congressional district: Republican minus Democratic share, in points. Bars above the line lean Republican, below lean Democratic.

Year	Winner	Party	Share	Margin
2024	Mike Bost	Republican	74.2%	48.4
2022	Mike Bost	Republican	75.0%	50.0
2020	Mike Bost	Republican	60.4%	20.9
2018	Mike Bost	Republican	51.6%	6.2
2016	Mike Bost	Republican	54.3%	14.6
2014	Mike Bost	Republican	52.5%	10.6
2012	William L. Enyart	Democratic	51.7%	8.9
2010	Jerry F. Costello	Democratic	59.8%	23.3
2008	Jerry F. Costello	Democratic	71.4%	46.5
2006	Jerry F. Costello	Democratic	100.0%	—
2004	Jerry F. Costello	Democratic	69.5%	40.6
2002	Jerry F. Costello	Democratic	69.2%	38.5
2000	Jerry F. Costello	Democratic	100.0%	—
1998	Jerry F. Costello	Democratic	60.4%	20.7
1980	Philip Crane	Republican	74.1%	48.2
1978	Philip Crane	Republican	79.5%	59.1
1976	Philip Crane	Republican	72.8%	45.7

2024

Candidate	Party	Votes	Share
Mike Bost Won	REP	272,754	74.19%
Brian Roberts	DEM	94,875	25.81%
Total		367,629

2022

Candidate	Party	Votes	Share
Mike Bost Won	REP	218,379	75.00%
Homer "Chip" Markel	DEM	72,791	25.00%
Nancy Foster	W	1	0.00%
Total		291,171

2020

Candidate	Party	Votes	Share
Mike Bost Won	REP	194,839	60.43%
Raymond C. Lenzi	DEM	127,577	39.57%
Total		322,416

Questions and answers

Who represents Illinois's 12th congressional district?

Mike Bost (Republican) is the current representative; the term ends on 2027-01-03.

Who won the last election in Illinois's 12th congressional district?

Mike Bost won in 2024 by 48.4 points.

Results: FiveThirtyEight, from official sources.