Gore wins in 2000

[Small Business Owner of Any Repute]

If Gore was president during 9/11, he immediately would have had 90% approval ratings, with Republicans falling over themselves to authorize whatever more-limited version of war Gore would have wanted. It's the "Rally Around the Flag" effect. When America is attacked, the President becomes bulletproof.

I'd presume Gore would have been re-elected, and with a larger margin than Bush was.