Giuliani seems to be leading the polls as the leading Republican candidate for President. Much of the enthusiasm for him seems to come from people who want a strong leader on national defense, and like him because of his actions during 9/11. As noted below, most of his support probably comes from fellow draft dodgers who feel guilty about avoiding the draft during Vietnam.
As a Vietnam veteran, I’m not happy about people who avoided the draft being touted as strong leaders on national security. Look at the mess we got with George Bush II (& Cheney) who ran on exactly that basis. This article links to several other articles about how Giuliani avoided the draft. I suspect that if he pushes 9/11 too hard, it will come back to haunt him; he talked a good game, but he didn’t really do much. The World Trade Center is still basically just a hole in the ground. That may not be Giuliani’s fault, but he didn’t solve the problem either. Casualties of 9/11 got Federal money; I don’t know that New York City did much for them. We’ll see how it plays.
The strength of Giuliani’s campaign has got to be embarrassing to Bush because the main reason that Giuliani gets so much credit for his performance after 9/11 was that Bush and Cheney were essentially missing in action immediately after the attacks.