2006Flipped from RepublicanFinal resultsIncumbent defeated
2006 election for South Dakota Legislative District 12
South Dakota State Senate · South Dakota
Sandy Jerstad (D) won with 50.1% of the vote, defeating William F. Earley (R) by 0.2 points, a seat Republicans won last time.
Sandy JerstadDemocrat · winner
50.1%5,175
William F. EarleyRepublican · incumbent
49.9%5,155
10,330 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 2006
Races before and after
Source: Harvard Dataverse / Carl KlarnerUpdated Sep 30, 2026, 7:29 AM ET