2020Flipped from DemocraticFinal resultsIncumbent defeated
2020 election for Illinois Representative District 45
Illinois House of Representatives · Illinois
Seth Lewis (R) won with 53.2% of the vote, defeating Diane Pappas (D) by 6.4 points, a seat Democrats won last time.
Seth LewisRepublican · winner
53.2%30,246
Diane PappasDemocrat · incumbent
46.8%26,590
56,836 votes
Source: MIT Election Data and Science LabUpdated Oct 1, 2026, 10:09 AM ET
The seat over time
D − R margin in this seat's races around 2020
Races before and after
Source: MIT Election Data and Science LabUpdated Oct 1, 2026, 10:09 AM ET