I just found an intriguing article by Michael Shermer from the October 2006 edition of Scientific American that discusses the links between various Christian denominations in the U.S.A., different political positions and acceptance of evolution as scientific fact.
The article quotes statistics from a 2005 Pew Research Center poll which showed that:
70% of Evangelicals are creationists compared to
32% of other Protestant denominations and
31% of Catholics
60% of Republicans are creationists, while only 11% accept evolution, compared to
29% of Democrats are creationists, while 44% accept evolution.
Comparing Liberals to Conservatives, the poll found 63% of liberals in America accept the fact of evolution, while only 37% of conservatives accept it.
I don't doubt that those numbers are possibly quite inaccurate, but they do give an indication of where the biggest problem lies in America with regards to intelligence and education. The Evangelicals and Republicans are sorely lacking in both.
I highly recommend reading the rest of the article, as it provides some insight into compatibility of evolution with theology and so on, if anyone is interested.