The 2010 Debrief · post-mortem · permanent archive
How did the polling industry do this cycle?
The 2010 industry MAE landed at 5.2pt — graded across 73 historical races with a known outcome — and 289 polls were analyzed across 108 pollsters. Signed bias +1.67pt: pollsters again systematically over-predicted Republicans.
INDUSTRY MAE
5.2pt
vs midterm avg
SIGNED BIAS
+1.67pt
R-leaning
POLLS · POLLSTERS
289
108 firms
RACES SCORED
73
w/ known outcome
Industry mean absolute error · 2002–2010
Per-pollster scorecard · 2010 · sorted by MAE
Signed bias · ±4.7pt
MAE · 0–6.7pt
Biggest-miss races · 2010
| Race | Expected | Actual | Miss | Direction |
|---|---|---|---|---|
| us-governor-2010-co | D+39.00 | D+14.67 | -24.3pt | D-margin overestimate |
| us-governor-2010-me | R+15.00 | R+1.70 | 13.3pt | R-margin overestimate |
| us-governor-2010-sd | R+11.00 | R+23.02 | -12.0pt | R-margin underestimate |
| us-governor-2010-tn | R+22.30 | R+31.95 | -9.7pt | R-margin underestimate |
| us-senate-2010-nv | R+3.50 | D+5.74 | 9.2pt | R-overestimate |
| us-senate-2010-md | D+18.00 | D+26.44 | 8.4pt | D-margin underestimate |
| us-senate-special-2010-wv | D+3.00 | D+10.07 | 7.1pt | D-margin underestimate |
| us-senate-2010-la | R+12.00 | R+18.89 | -6.9pt | R-margin underestimate |