I think Rudy would win NY state. He was able to win elections in the city, which leans Democratic. The Republicans tend to do better upstate, so Rudy would probably win the upstate areas. I think he'll run and win for Governor in 2006, so he'll have a real statewide following by 2008. He'd do far better than the average Republican across the board, and then factor in the home state thing, and I think he'd win.
People who say he'd have trouble in the south are right, though, so the election would be very close. Unless there was a southern runnin mate...
Guliani did win as mayor of NY, but he beat Dinkins in decline and then Messinger who was an asbolutley horrible candidate. Guliani declined to run again due to health reasons, he would have been re elected because of 9/11 if he did run, but if he did run for re-election & 9/11 did not happen he would have lost (wll he may have won if Green boon doggled his campaign the way he did against Bloomberg).
In 08 (although it won't happen since Kerry will win 04:) Edwards could take New York. Guliani did a hell of a job after the 9/11 attacks, but I don't know how much of an impact that would be 7 years later. Also it would be tough for him to win NYC despite 9/11. He did win as mayor twice, but that was against 1 mayor in decline in Dinkins, and a terrible candiate in Messenger, The turnout was low among Democrats both times, with Edwatds it would be a much bigger challenge to Rudy because Edwards is 100x the candidate than anyone else he has beaten was.