The Electoral College as it stands Oct. 27.
Four times in American history, the presidency has gone to a candidate who did not win the popular vote.
In 1824, John Quincy Adams lost the popular vote to Andrew Jackson.
In 1876, Samuel Tilden won the popular vote against Rutherford B. Hayes, but Hayes beat Tilden by a single vote in the Electoral College.
Like Us on Facebook
In 1888, incumbent president Grover Cleveland beat challenger Benjamin Harrison in the popular vote, but lost a to a landslide Harrison victory in the Electoral College.
And in 2000, Al Gore lost Florida and the presidency when George W. Bush beat him in electoral votes despite a close win for Gore in the popular vote.
An Electoral College/popular vote split may happen again this year, as President Obama consistently trails Republican challenger Mitt Romney in national polls.
But Obama has a steady lead in important swing states and in Electoral College predictions.
Right now, Obama is poised to take 201 electoral votes to Romney's 191, with 146 still undecided.
While the unassigned electoral votes are more than enough to swing the election to either candidate, polls in most swings states have been trending away from the mean.
Romney is gaining support in the South and some rural states, while Obama holds a stable lead in the Rust Belt, including the critical swing state of Ohio.
If we assign electoral votes based on current polling, Obama wins with 277 votes. Colorado and Virginia are still undecided, but even winning both states isn't enough for Romney to overtake Obama.
That translates to a 51.5 percent share for Obama of all available electoral votes, compared to 48.5 percent for Romney.
In contrast, Romney is polling nationally about 1 percent above the president.
FiveThirtyEight gives Obama a 74.4 percent chance to take the Electoral College and the presidency. That's down from a high of 87.1 on Oct. 4, right before the fallout from the first presidential debate saw Romney's ratings rise.
But Obama's odds are up from a low of 61.1 percent on Oct. 12, and they have been rising ever since.
The prediction market Intrade, which allows betting on future events like the presidential election, puts Obama's chances of winning the Electoral College at 62.8 percent, lower than FiveThirtyEight's prediction, but still far higher than Romney's 37.3 percent chance.
This all assumes that Obama takes Ohio.
The president is polling at a little over 2 percent above Romney in the state, and while the president's margin is small, it has been consistent.
Without Ohio, Romney must win several smaller states that look quite blue right now, while still holding onto tenuous support in his own red roster.
>> Latest Electoral College Map: Tough Math For Romney After North Carolina Changes Its Mind; Can He Swing Enough States?
>> Presidential Polls 2012 - Swing States: Florida Looking Better for Romney, But Can He Secure His Lead?
>> Latest Electoral College Map Shows North Carolina Is a Swing State Again, Lessons for Virginia and Florida?
>> Don't Call It A Comeback: Romney's Momentum in the Polls Fades, But Not Because of Obama