I originally posted this as a comment, but people asked me to make a diary, so I am. This is my analysis of the right wing handwringing over the supposed polling bias, specifically in PA, which make a good case study because (1) it is a state that has plenty of polling, (2) there is a clear power struggle going on there over whether it is a swing state with the PA RSC trying not to lose millions in outside spending and (3) there is a GOP pollster actually touting the "bias" in the PA polling and claiming to poll the state as a 1 or 2 point race. Anyway, here it is.
I compared polls in PA, one of the "Quinnipiac three" that the wingnuts are particularly whiny about. In this case, we actually have a PA GOP pollster, Susquehanna, touting the poll bias:
http://sprblog.wordpress.com/....
In our surveys, 18-44 yr. olds make up 30% of all interviews and voters 45 years of age and older represent the remaining seventy percent. For instance, according to 2008 exit polls voter turnout among 18-29 year olds peaked at 18%, but national and state polling proves interest among younger voters down sharply this year due to higher unemployment with younger voters and college graduates in particular.
[R]ecent polls showing a double-digit lead for Obama are not believable, and are probably using the 2008 voter turnout as the basis of their survey model. ... Our vote model for gauging the number of interviews conducted with voters of different demographic groups (things like party affiliation, racial background and age range, etc.) is a blend of turnout models from both the 2008 and 2004 presidential elections, but leans more towards 2004 VTO and is predicated on the belief that turnout this November will not be anywhere near ’08 levels when 5.9 million votes were cast.
I decided to do some research on these claims. Here are the PA exit polls on age:
http://elections.nytimes.com/....
http://www.cnn.com/....
Age 2008 2004 Weighted (75% 2004)
18-29 18% 21% 20%
30-44 28% 28% 28%
45-64 39% 29% 32%
65+ 15% 22% 20%
The Q poll didn't have the detailed crosstabs, but I used an F&M poll that showed Obama +9:
https://edisk.fandm.edu/....
Guess what?
Age F&M
18-34 12%
35-44 12%
45-64 40%
65+ 37%
F&M severely undersampled young voters, even compared to just 2004.
By Race
Race 2008 2004 Weighted
White 81% 82% 82%
Black 13% 13% 13%
Race F&M
White 91%
Black 9%
By Geography
Region 2004 F&M
Philly 12% 9%
SE 21% 24%
NE 14% 12%
Pitt 23% 20%
"T" 30% 35%
2008 didn't have region in the exits, so I just used 2004.
So, the F&M poll compared to the 2004/2008 weighting that Susquehanna suggests they used (or even to just the 2004 exit polls alone...) UNDERSAMPLES young voters, black voters, and Philadelphia and oversamples the "T" area of Pennsyltucky. Yet, when you look at voter self-identification:
Voter ID 2004 2008 F&M
Dem 41% 44% 41%
GOP 39% 37% 29%
Ind 20% 18% 30%
Despite FAVORABLE demographics for the GOP, MUCH more favorable than even 2004, the voter self-identification in PA has gone from +2 to +7 to +12 from 2004 to 2008 to 2012. There is no manufactured bias in these polls, there is just manufactured outrage on the right. The GOP, at least in PA, is absolutely hemorraging support.