Pure fantasy. Did anyone notice the quality of the campaign Rudy ran last time. Epic fail.
He couldn't take a state, he's too Liberal for the GOP, he's extremely old news, he hasn't held elected office since 2002, and he hasn't held anything above the level of Mayor. Therefore, he can't win. The best possible Rudy scenario Alternate history wise is that Republicans lost in 2000 and he's the 2004 nominee. Either that, or Rudy is elected to the Senate or the Governorship sometime post-9/11. Rudy's claim to the Republican nomination would be better if he had decided to run for the Senate in 2010 against Kirsten Gillibrand and won. Giuliani decided against it, and is most likely leaving the political scene for good.