2008Final results
2008 election for Illinois's 18th District
U.S. House · Illinois
Aaron Schock (R) won with 58.9% of the vote, defeating Colleen Callahan (D) by 20.9 points.
Aaron SchockRepublican · winner
58.9%182,589
Colleen CallahanDemocrat
37.9%117,642
Sheldon SchaferGreen
3.2%9,857
310,088 votes
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 7:25 AM ET
The seat over time
D − R margin in this seat's races around 2008
Races before and after
Source: MIT Election Data and Science LabUpdated Sep 30, 2026, 7:25 AM ET
Money in this race
Each line compares the two campaigns on one scale.
Colleen CallahanAaron Schock
$624.5K
Raised by the campaign
$2.6M
$607.7K
Spent by the campaign
$2.6M
$16.8K
Cash on hand
$46.1K
Other candidates' campaigns: Sheldon Schafer $9.2K.
Campaign money: FEC, through Dec 31, 2008.
Source: FEC campaign filingsUpdated Dec 31, 2008