In which Creationism and Evolution Overlap

My local newspaper (The Pasadena Star News) had an AP article today about how science museums are (or aren't) responding to the onslaught of creationism and Intelligent Design. At the bottom of the column were results from a Sept. 8-11 Gallup Poll:

58% of people believe Creationism is definitely or probably true. 55% of people believe Evolution is definitely or probably true.

Assuming the maximum margin of error of 3%, it seems to me that 7% of the sample believe equally in Creationism and Evolution. Since those ideas can't BOTH be true (trust me on that), I suggest we believe one of the following:

1) Some people answer polls without thinking.
2) Some people are happy holding contradictory opinions.
3) The Gallup poll writes confusing questions.
4) Newspaper editors can't add.

I couldn't find raw Gallup data online, but the Baptist News seems happy with the results. (They mention the same numbers, but as part of an August poll, at the bottom of this article.)

Religion
Media
Pictures of Plants