National polls still show Republican challenger Mitt Romney leading by a slight margin over President Obama, but swing state polls show continued solid support for the president, especially in the states where it matters most.
Romney recently flipped North Carolina, which voted for Obama in 2008, moving it into his column after a sustained series of polls showed his support growing higher than Obama will be able to undo before the election.
That moved Romney into the lead in the Electoral College count, though only by 5 votes.
Romney is also polling well in Florida, though a few recent polls show Obama may be gaining back some of the votes he's lost since his poor performance in the first presidential debate.
Tonight's presidential debate is in Boca Raton, Fla., so it may have a disproportionate effect on that state.
But a slew of recent polls show Obama with the lead in the critical swing state of Ohio, some saying he is up as much as 5 points. While Ohio has only 18 electoral votes, compared to Florida's 29 or Pennsylvania's 20, FiveThirtyEight predicts it has a better than 40 percent chance to be the state that provides the necessary electoral votes to the eventual winner.
No Republican has ever won the White House without Ohio, and while Romney can do it, that road runs through several difficult swing states for him.
Even if Romney takes the entire South, including his latest prize of North Carolina and likely victories in Florida and Virginia, he will still be 22 electoral votes shy of winning the presidency outright.
But at that point, he has exhausted all his low-hanging fruit.
The next largest pot of votes is Pennsylvania, and it's likely that state will be called for Obama in the next week. Only one recent poll has shown a Romney lead there, and it has been an outlier for at least a month, well before the first presidential debate.
If Romney doesn't succeed in Ohio, he'll need to grab Wisconsin or Michigan, with 10 and 16 electoral votes, respectively.
But Wisconsin's union troubles have made Republicans unwelcome there, and while Romney's father was governor of Michigan, the auto-industry bailout signed by Obama and opposed by Romney is very popular in Michigan.
Romney could take all the rest of the swing states to win, but that means beating Obama in Nevada, Colorado, Iowa and New Hampshire.
While Romney has had good news in New Hampshire recently, and Colorado is still very much in the air, both Nevada and Iowa have been moving in Obama's direction.
But all this is moot if Romney can't hold on to Florida. Without Florida, Romney would need to take Ohio, Wisconsin and Michigan, as well as grab one other state.
And without Florida or Ohio, Romney must win everywhere else, an extremely unlikely scenario.
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