Denial: It Ain't Just a Swing State in Egypt
I think this explains a lot:

Even after the final report of Charles Duelfer to Congress saying that Iraq did not have a significant WMD program, 72% of Bush supporters continue to believe that Iraq had actual WMD (47%) or a major program for developing them (25%). Fifty-six percent assume that most experts believe Iraq had actual WMD and 57% also assume, incorrectly, that Duelfer concluded Iraq had at least a major WMD program. Kerry supporters hold opposite beliefs on all these points.

Similarly, 75% of Bush supporters continue to believe that Iraq was providing substantial support to al Qaeda, and 63% believe that clear evidence of this support has been found. Sixty percent of Bush supporters assume that this is also the conclusion of most experts, and 55% assume, incorrectly, that this was the conclusion of the 9/11 Commission. Here again, large majorities of Kerry supporters have exactly opposite perceptions.

These are some of the findings of a new study of the differing perceptions of Bush and Kerry supporters, conducted by the Program on International Policy Attitudes and Knowledge Networks, based on polls conducted in September and October.

Steven Kull, director of PIPA, comments, "One of the reasons that Bush supporters have these beliefs is that they perceive the Bush administration confirming them. Interestingly, this is one point on which Bush and Kerry supporters agree." Eighty-two percent of Bush supporters perceive the Bush administration as saying that Iraq had WMD (63%) or that Iraq had a major WMD program (19%). Likewise, 75% say that the Bush administration is saying Iraq was providing substantial support to al Qaeda. Equally large majorities of Kerry supporters hear the Bush administration expressing these views--73% say the Bush administration is saying Iraq had WMD (11% a major program) and 74% that Iraq was substantially supporting al Qaeda.

...Kull continues, "To support the president and to accept that he took the US to war based on mistaken assumptions likely creates substantial cognitive dissonance, and leads Bush supporters to suppress awareness of unsettling information about prewar Iraq."

So here we have people either supporting the president because they believe certain things pretty conclusively proven to be untrue, or believing these things because they support the president so uncritically that they choose to believe him rather than their own lyin' eyes.

If the second formulation is correct, I don't know what's to be done: misplaced faith, in the face of demonstrable reality, is more an obstacle to skirt than a problem to solve. If it's the former, though, then maybe Bush is right after all: education is the key. Not that the administration/campaign (now more than ever, they're pretty clearly one and the same) is likely to disabuse them of these notions.