A recent poll seems to have slipped under the radar except in academic circles, or maybe I just missed it:
A few months ago, the Tobin Project sponsored a YouGov poll to be put in the field on American attitudes towards foreign policy and national security. Dartmoth political science Benjamin Valentino conducted the poll....There's a lot in this poll that might be of interest to you, depending on your interests, but (via Jim Lobe) I'd just like you to know that 63% of Republicans still think Iraq had WMDs in 2003 (click to enlarge):
You can look at all of the topline results here, with party-line breakdowns to the responses....

And (as noted by Daniel Drezner) that birth-certificate thing is still an open question in the GOP, with more than 63% of Republicans now believing Obama is foreign-born, and nearly 15% of the rest saying they don't know (click to enlarge):

Yes, 8% of Republicans used to think Obama was eligible to be president by birth, but now think he wasn't, in addition to the more than 55% who say they never thought he was eligible by birth.
Dear Beltway elite: both sides do not do it. Republicans are crazy.
(Via Juan Cole and Reza Marashi on Twitter.)