VotePredictor
past elections

Iowa Senate

David Osterberg (D) vs Chuck Grassley (R)

Actual result
R+37.9
Final polls said
R+44.0
1 late poll · ✓
Model predicted
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+44.06.1
2Selzer & Co.R+44.06.1

Polls (3)

PollsterDatenPollMiss
Mason-Dixon Polling & Strategy1998-10-26803R+44.06
Mason-Dixon Polling & Strategy1998-10-12809R+45.07
Selzer & Co.1998-09-09800R+44.06