2008 Senate · MA
SurveyUSA · fieldwork ended 2008-10-27 (8 days before the election) · 658 respondents · IVR
The poll said
Democrat 58% · Republican 34%
D+24.0
The certified result
Democrat 63.55% · Republican 29.84%
D+33.7
The arithmetic
- Poll margin = 58 − 34 = 24.00
- Actual margin = 63.551 − 29.844 = 33.707
- Signed miss = 24.00 − (33.707) = -9.707
- Absolute miss = |-9.707| = 9.707
The poll overstated the Republican by 9.7 points and had the right leader.
Where these numbers come from
Poll and result: 538 raw_polls.csv. Poll ID 16606, race ID 1559 (538 database).