Poll Accuracy in the 2008 Presidential Election
—Initial Report, November 5, 2008—
Costas Panagopoulos, Ph.D.
Department of Political Science
Fordham University
For inquiries: cpanagopoulo@fordham.edu or (917) 405-9069
For all the derision directed toward pre-election polling, the final poll estimates were not
far off from the actual nationwide voteshares for the two candidates. On average, preelection
polls from 23 public polling organizations projected a Democratic advantage of
7.52 percentage points on Election Day, which is only about 1.37 percentage points away
from the current estimate of a 6.15-point Obama margin in the national popular vote.
Following the procedures proposed by Martin, Traugott and Kennedy (see Public Opinion
Quarterly, Fall 2006, pp. 342-369) to assess poll accuracy, I analyze poll estimates from
these 23 polling organizations. Four of these polls appear to have overestimated McCain
support (indicated with a * below), while most polls (17) overestimated Obama strength.
Pre-election projections for two organizations’ final polls—Rasmussen and Pew—were
perfectly in agreement with the actual election result (**).
The following list ranks the 23 organizations by the accuracy of their final, national preelection
polls (as reported on pollster.com).
1. Rasmussen (11/1-3)**
1. Pew (10/29-11/1)**
2. YouGov/Polimetrix (10/18-11/1)

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