1980Flipped from DemocraticFinal resultsIncumbent defeated
1980 election for Ohio Senate District 10
Ohio State Senate · Ohio
Michael DeWine (R) won with 60.6% of the vote, defeating John K. Mahoney (D) by 21.2 points, a seat Democrats won last time.
Michael DeWineRepublican · winner
60.6%66,884
John K. MahoneyDemocrat · incumbent
39.4%43,479
110,363 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 1980
Races before and after
Source: Harvard Dataverse / Carl KlarnerUpdated Sep 30, 2026, 7:29 AM ET