I expect a last-minute "surprise" by the democrats similar to the DUI story that came out the weekend before the 2000 election.
No idea what it will be, but the RATS have thousands of lawyers, hundreds of private investigators, plenty of George Soros' money to incent folks to dig up the dirt, and a near monopoly in the news media to help sling the mud.
Would suprise me if they just make something up, release it on Sunday 31 or Monday the 1st. In the scramble to fully refute it the word won't get out that it's phony until after the election. It's a win/win for them. If Kerry wins, nothing else matters, if Bush wins they'll print a retraction saying they were misled.