There are no fewer than 33 mathematical formulas by which the Electoral College winds up in a 269-269 tie. With most polls at or near dead-even, most experts agree it's worth at least preparing for the possibility of a dead-even electoral vote in the battleground states.
"These states could split between these two men. They could go all Bush, or they could go all Kerry — it's a ‘who knows’ situation in many of these swing states!" says Andrew Kohut of the Pew Research Center.
The Decision Desk at NBC News sees the map with nine toss-up battleground states — Florida, Iowa, Minnesota, Nevada, New Hampshire, New Mexico, Ohio, Pennsylvania and Wisconsin. Under a number of combinations, with Bush winning one cluster and Kerry another, both men end up at 269, one short of the 270 needed.
The first question is: What happens then? The election goes to the House of Representatives, where each state would get one vote. While Bush would likely win, there is a wild scenario under which a newly elected Democratic-controlled Senate would hand President Bush John Edwards as his vice president.
"Now, if the new Senate could possibly be Democratic, the Senate chooses the vice president in the case of a tie," says constitutional law expert Rick Pildes. "Presumably, they would choose John Edwards. That's how you'd end up with President Bush, Vice President John Edwards."
And there may be an even bigger problem if the electoral vote ends up tied. Many experts feel it's bad for all of us.
"This is going to be a real challenge to this country in a situation where the public has such strong feelings about these two candidates," says Kohut. "If someone doesn't come away as the decisive, legitimate winner in the minds of the American public."
Legitimate or not, it's legal.
"It's complicated and it's interesting, but it's all there in the Constitution," says Stephen Hess of the Brookings Institution.
There's an even wilder scenario that's possible. In the event of a tie in the electoral vote and then a tie in the House of Representatives, John Edwards could be de-facto president for two years until a new House of Representatives election.
But first things first — America has to get through Election Day.
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