WASHINGTON - It happened in 2000, and only three times in history before that, but this year it could happen again.
One presidential candidate could win the popular vote while the other wins the Electoral College.
Democrat Al Gore won the popular vote in 2000, but former President George Bush took the presidency by winning more electoral votes.
"It does not come down to the popular vote, it comes down to the Electoral College. E very now and then you have a candidate who wins the Electoral College but loses the popular vote," says University of Mary Washington Political Scientist Steve Farnsworth.
To win the presidential election, a candidate needs 270 electoral votes. Those votes come from an individual state's electors who've pledged to vote for whomever wins the state.
In states affected by Superstorm Sandy, including New York and New Jersey where President Barack Obama is favored to win, popular vote totals may be low.
"It's going to reduce his numbers nationally and make it possible that we could have a split outcome," says George Mason University Political Scientist Mark Rozell.
But, Rozell says, several scenarios could keep the president in the White House even if he gets fewer votes nationally than Republican Mitt Romney.
According to Farnsowrth, "big margins in one place, say for example, for Obama in Maryland, is going to be smaller than the big margins that Romney might get in the states like Alabama and Mississipi and Tennesse."
The right mix of states, despite a popular vote loss, could determine which candidate wins.
"If it happens twice in 12 years, it's going to raise a lot of concerns about whether we can continue to have an Electoral College system," says Rozell.
Here's a look at presidential elections in which the popular vote winner lost the race in the Electoral College:
- 1876: Republican Rutherford Hayes defeats Samuel Tilden by 185 to 184 in
Electoral College despite a 254,235-popular-vote deficit.
- 1888: Republican Benjamin Harrison defeats Democrat Grover Cleveland by
233 to 168 in Electoral College despite 90,596-popular-vote deficit.
- 2000: Republican George W. Bush defeats Democrat Al Gore by 277 to 266 in Electoral College despite 543,895-popular-vote deficit.
Here's a look at squeakers in presidential elections over the past century, in which the winner collected fewer than 300 Electoral College votes:
- 1916: Democratic incumbent Woodrow Wilson defeats Republican Charles
Hughes 277 to 254.
- 1976: Democrat Jimmy Carter defeats Republican incumbent Gerald Ford
297 to 240.
- 2000: Republican George W. Bush defeats Democrat Al Gore 271 to 266.
- 2004: Republican incumbent George W. Bush defeats Democrat John Kerry 286 to 251.
(Copyright 2012 by WTOP and The Associated Press. All Rights Reserved.)