"On Sept. 18, 2002, CIA director George Tenet briefed President Bush in the Oval Office on top-secret intelligence that Saddam Hussein did not have weapons of mass destruction, according to two former senior CIA officers. Bush dismissed as worthless this information from the Iraqi foreign minister, a member of Saddam's inner circle, although it turned out to be accurate in every detail. Tenet never brought it up again."
Won't matter though. Whoever the 36% are that still support him will still support him - in fact I think at this point they'd support him even if he was found in bed on national live television with both a live boy and a dead girl.
He'd give the boy and girls parents the Medal of Freedom and that would be that.
Actually as I think of it his approval ratings would likely rise after such an event. Could get all the way up to 50% again.
Nothing makes the American public happy like dead girls and live boys.