Cook Political
Forecaster quality, broken out by office and by cycle. Scored on the Brier score of its final pre-election win probability (lower is better), over 615 races, 2016–2024.
Head-to-head vs VotePredictor Elections
Apples-to-apples: on the 615 races Cook Political forecast, its win-probability Brier vs VotePredictor Elections' calibrated win-prob on those same races.
| Model | Brier | Called right |
|---|---|---|
| Cook Political | 0.081 | 89% |
| VotePredictor Elections | 0.088 | 89% |
Every race (615)
Each race Cook Political scored, with its final pre-election call vs who actually won, and the Brier score for that call. Click a race for its full detail.
By office
| Office | Races | Brier | Called right |
|---|---|---|---|
| House | 333 | 0.101 | 96% |
| Senate | 140 | 0.070 | 98% |
By cycle
| Year | Races | Brier | Called right |
|---|---|---|---|
| 2016 | 84 | 0.055 | 95% |
| 2018 | 170 | 0.092 | 97% |
| 2020 | 165 | 0.086 | 97% |
| 2022 | 96 | 0.095 | 99% |
| 2024 | 100 | 0.065 | 99% |
Why no “time to election” curve? Unlike pollsters — where we have every poll with its field dates — our forecaster archive (JHK Forecasts) stores only each outfit's final pre-election forecast per race, not its earlier snapshots. So a lead-time breakdown genuinely isn't in the data for forecasters. Pollster pages do show it (e.g. the leaderboard).