VotePredictor
past elections

California House

Mike Levin (D) vs Diane L. Harkey (R)

Actual result
D+12.8
Final polls said
D+10.9
2 late polls · ✓
Model predicted
D+5.9
Winner
Dem

"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
1University of California Berkeley Institute of Governmental StudiesD+14.01.2
2The New York Times/Siena CollegeD+14.71.9
3SurveyUSAD+7.05.8
4VotePredictorD+5.96.9
5Public Opinion StrategiesD+2.010.8

Forecasters — pre-election win probability, scored by Brier

#ForecasterWin probBrierCalled
1FiveThirtyEightDem 97%0.001
2The EconomistDem 95%0.003
3Cook PoliticalDem 90%0.010
4Sabato's Crystal BallDem 90%0.010
5VotePredictorDem 88%0.014
6DDHQ/Decision DeskDem 82%0.032

Polls (5)

PollsterDatenPollMiss
SurveyUSA2018-10-31500D+7.06
The New York Times/Siena College2018-10-21500D+14.72
The New York Times/Siena College2018-09-20507D+9.73
University of California Berkeley Institute of Governmental Studies2018-09-20551D+14.01
Public Opinion Strategies2018-09-19400D+2.011