DHM Research
Graded against the actual result across 17 races (from 27 polls, through 2022).
Head-to-head vs VotePredictor Elections
The fair, apples-to-apples test: on the 12 races DHM Research actually polled, how its final poll's margin compared to what VotePredictor Elections predicted for those same races.
| Model | Avg miss (pts) | Called right |
|---|---|---|
| DHM Research | 2.63 | 92% |
| VotePredictor Elections | 2.39 | 92% |
VotePredictor Elections aggregates all the pollsters, so it's expected to beat any single one on margin — that's the value of averaging. The honest comparison among forecasters is on the combined board.
Every race (17)
Each race DHM Research polled, scored on its final poll — the call right before the vote — against the actual Dem−Rep result. Click a race for its full detail.
| Race | Their call | Result | Miss | Call |
|---|---|---|---|---|
| 2022 OR Governor | R+1.0 | D+3.4 | 4.4 | ✗ |
| 2020 OR President | D+12.0 | D+16.1 | 4.1 | ✓ |
| 2018 OR Governor | D+5.0 | D+6.4 | 1.4 | ✓ |
| 2016 OR Governor | D+9.0 | D+7.2 | 1.8 | ✓ |
| 2016 OR President | D+7.0 | D+11.0 | 4.0 | ✓ |
| 2014 OR Senate | D+21.0 | D+18.9 | 2.1 | ✓ |
| 2012 OR President | D+7.0 | D+12.1 | 5.1 | ✓ |
| 2010 OR Governor | D+3.0 | D+1.5 | 1.5 | ✓ |
| 2008 OR President | D+19.0 | D+16.3 | 2.7 | ✓ |
| 2008 OR Senate | D+5.0 | D+3.4 | 1.6 | ✓ |
| 2006 OR Governor | D+7.0 | D+8.0 | 1.0 | ✓ |
| 2004 OR President | D+6.0 | D+4.2 | 1.8 | ✓ |
| 2002 OR Governor | D+6.0 | D+2.9 | 3.1 | ✓ |
| 2002 OR Senate | R+19.0 | R+16.6 | 2.4 | ✓ |
| 2000 OR President | D+1.0 | D+0.4 | 0.6 | ✓ |
| 1998 OR Governor | D+53.0 | D+34.4 | 18.6 | ✓ |
| 1998 OR Senate | D+52.0 | D+27.3 | 24.7 | ✓ |
Accuracy by time to election
Lower is better. Time to election runs right (election week) to left (~2 months out).
By the numbers
| Time to election | Polls | Avg miss | vs field | Called right |
|---|---|---|---|---|
| 1–3 wk | 11 | 2.60 | -2.47 | 91% |
| 3–6 wk | 10 | 6.73 | +0.99 | 100% |
| 6–9 wk | 5 | 4.35 | -1.80 | 60% |
vs field is this pollster's average miss minus all pollsters' at the same lead time — green beats the field, redtrails it. Our historical polls reach ~2 months out; earlier polling isn't in the record.
Track record by cycle — getting better?
| Year | Polls | Avg miss | Lean (house effect) |
|---|---|---|---|
| 2002 | 4 | 2.8 | R+0.6 |
| 2008 | 4 | 4.3 | R+2.1 |
| 2016 | 4 | 3.9 | R+0.1 |
Do we credit a pollster for fixing its bias? Each cycle, the model re-estimates every pollster's lean from all its earlier polls (walk-forward) and subtracts it before using the poll. We tested weighting recent cycles more — it doesn't help: a pollster's lean in one cycle barely predicts the next (correlation 0.28), so the swings above are mostly noise, and averaging over more history beats chasing the latest cycle. The all-time estimate we use came out within ~0.5% of the best option.