Well he was within a whisker of becoming president thanks to hanging chads in Florida. He first of all conceded, then unconceded (if such a word exists). He nearly tore the country apart.
See #11 this thread. Great minds and all that.
He was closer earlier. A mere 17 votes more and he'd have been President. But there were no hanging chucks. Neither Schumer nor any others from his old Rat Senate buddies were willing to vote for him over Bubba. Seeing as he could have taken over, finished Bubba's and then run for two more terms on his own, it was a stunning no confidence vote against Gore.