2015Final resultsSpecial election
2015 special election for Illinois's 18th District
U.S. House · Illinois
Darin LaHood (R) won with 68.9% of the vote, defeating Rob Mellon (D) by 37.7 points.
Darin LaHoodRepublican · winner
68.9%35,329
Rob MellonDemocrat
31.1%15,979
51,308 votes
Source: Federal Election CommissionUpdated Oct 3, 2026, 3:20 AM ET
The seat over time
D − R margin in this seat's races around 2015
Races before and after
Source: Past results: 99chambers results archive (MEDSL, Klarner, state election offices)