As promised, a few links. When examining any polling data, employ a healthy skepticism. Has the news source reporting the poll interpreted the data accurately and fairly? Was the poll rigorously conducted? Is its methodology available? What is the reputation of the polling firm? The poll sponsor? (And how can you find out?) Might the poll have been affected by the wording of the questions or certain rhetorical constraints and contingencies?
Washington Times, “Poll Finds Doubts on Obama’s Birth”
NBC Washington, “53 Percent of Likely Va. Voters Think Obama Was Born in US”
Fayetteville Flyer, “Less Than Half of Arkansans Think Obama is a US Citizen”
Washington Independent, “How Many Southern Whites Believe Obama Was Born in America?”
Sources for the above:
Public Policy Poling, Virginia survey | Arkansas survey | “A Deeper Look at the Birthers”
The Daily Kos/Research 2000 Poll that started it all. [Daily Kos is a liberal webforum, Research 2000 a non-partisan polling company. But don't take my word for it; trust but verify.]
Some reactions here and here from Free Republic, a conservative webforum.