2012Final results
2012 election for Illinois Legislative District 25
Illinois State Senate · Illinois
Jim Oberweis (R) won with 57.5% of the vote, defeating Corinne M. Pierog (D) by 15.0 points.
Jim OberweisRepublican · winner
57.5%51,527
Corinne M. PierogDemocrat
42.5%38,061
89,588 votes
Source: Harvard Dataverse / Carl KlarnerUpdated Sep 30, 2026, 7:29 AM ET
The seat over time
D − R margin in this seat's races around 2012
Races before and after
Source: Harvard Dataverse / Carl KlarnerUpdated Sep 30, 2026, 7:29 AM ET