2010Flipped from DemocraticFinal resultsIncumbent defeated
2010 election for Minnesota Senate District 4
Minnesota State Senate · Minnesota
John Carlson (R) won with 54.5% of the vote, defeating Mary Olson (D) by 9.2 points, a seat Democrats won last time.
John CarlsonRepublican · winner
54.5%18,956
Mary OlsonDemocrat · incumbent
45.3%15,752
34,763 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 2010
Races before and after
Source: Harvard Dataverse / Carl KlarnerUpdated Sep 30, 2026, 7:29 AM ET