In another example of the kind of uncertainty I mentioned around that seemingly sacrosanct number of 537 votes that Bush "lost" by in Florida the "popular" election (I hate even referring to it as an election, save that it works as a reference since it seems to resonate as real to some folks despite there being no such thing), there's this article on dual registrations of some voters.
Thousands Registered to Vote in 2 States-Report
About 46,000 people are registered to vote in two states, New York and Florida, a violation of both states' laws that could affect the outcome of the November presidential election, according to an investigation by the Daily News.
Throwing further doubt on the question of which way the vote would have gone in subsequent recounts:
Of the 46,000 registered in both states, 68 percent are Democrats, 12 percent are Republicans and 16 percent didn't align themselves with a party, the newspaper reported on Sunday.
There's just no way to say that it was exactly 537 votes, or that even if 600 more votes had been cast and agreed on to make Gore the winner, that it would have resolved the issue. If the dual votes were tossed out (and not just in one state, since this would constitute fraud the votes would be eliminated from the count altogether), the majority of votes lost would have been for Gore.
Note this also:
The duel registrations have gone undetected because election officials do not check voter rolls across state lines, the newspaper said.
So far as I know (and this of course could be changing), that isn't going to change with electronic voting.