Bush didn't appoint any justices his first term. We couldn't know that in 2000, of course, but if we could have, maybe some of us wouldn't have voted for him.
Gore would have sailed to re-election in 2004. The economy was strong, he likely would have done something militarily in response to 9/11 whereby people would love him, even conservatives. Then, we’d have put McCain against him. Game, set, match.