VotePredictor
past elections

South Dakota Senate

Jay H. Williams (D) vs John R. Thune (R)

Actual result
R+43.7
Final polls said
R+29.6
5 late polls · ✓
Model predicted
R+34.8
Winner
Rep

"Final polls said" averages polls from the last ~3 weeks — the call right before the vote, and how pollsters are rated. The model's prediction is walk-forward (trained only on earlier races).

Final rankings

How everyone who called this race did, ranked — VotePredictor shown inline (★).

Pollsters — each pollster's final poll vs the result

#PollsterFinal callMissCalled
1Mason-Dixon Polling & StrategyR+38.05.7
2VotePredictorR+34.88.8
3SurveyMonkeyR+34.09.7
4Remington Research GroupR+21.022.7
5Nielson Brothers PollingR+19.024.7

Forecasters — pre-election win probability, scored by Brier

#ForecasterWin probBrierCalled
1Cook PoliticalRep 99%0.000
2FiveThirtyEightRep 100%0.000
3Inside ElectionsRep 99%0.000
4Sabato's Crystal BallRep 99%0.000
5VotePredictorRep 100%0.000

Polls (5)

PollsterDatenPollMiss
SurveyMonkey2016-11-04459R+34.010
SurveyMonkey2016-10-28298R+36.08
Nielson Brothers Polling2016-10-25600R+19.025
Remington Research Group2016-10-201115R+21.023
Mason-Dixon Polling & Strategy2016-10-19400R+38.06