Coleman +10 or -9?

Friday, one poll showed Republican Sen. Norm Coleman leading by 10 points in Minnesota. Saturday, another poll showed Coleman's Democratic challenger Al Franken leading by nine points.

Obviously, both polls cannot be right. The phrasing or sequence of questions can influence answers. Beyond that, there was one difference in the two polls: The poll released Friday was conducted Tuesday and Wednesday, while the poll released Saturday also included surveys taken Thursday, after Coleman voted for the unpopular bailout.