Wow, do you have links to the polls? I didn’t think the number was that high.
On FR, this percentage is likely greater than 92%:
CNN poll on Obama: 6 of 10 doubt U.S. birth story
"A new poll by CNN, whose editorial commentary largely supports President Obama and his policies, delivered some bad news on his apparent birthday today: 6 of 10 people are uncertain the president was even born in the United States.
The poll was taken July 16-21 of 1,018 adults, including 335 Democrats and 285 Republicans. It has a margin of error of 3 percentage points."....
CNN even over-polled Democrats...as usual.