The math in the fight over the Electoral College is getting tighter, and the campaigns face difficult decisions about where best to spend their limited funds.
This week, consistently good polls for Republican challenger Mitt Romney in North Carolina culminated in RealClearPolitics calling the state for him.
FiveThirthyEight also gives Romney an 82.7 percent chance to win the state in November.
That moves Romney into the lead for assigned electoral votes with 206, compared to President Obama's 201, with 131 votes up for grabs.
However, recent polls in other swing states leaned heavily toward Obama this week.
The president led in polls in Colorado, Iowa, Wisconsin, Michigan, Nevada and New Hampshire.
In addition, his strong showing in Pennsylvania will likely result in reputable sources calling the state for him, possibly next week.
Pennsylvania is essentially a must-win for Obama, as he is counting on its 20 electoral votes to get him close to the 270 he needs to win.
And if he doesn't win Pennsylvania, it's not likely he'll carry other similar Rust Belt states in which he isn't as far ahead.
But very good news for Romney in Florida, as no less than four polls showed him leading there. In the same way that Obama needs Pennsylvania, Romney needs Florida, as its whopping 29 electoral votes are the largest prize remaining on the map.
While Florida was the center of the electoral struggle in 2000, Ohio is the star this year.
Even if Romney takes Florida and Obama takes Pennsylvania, the race is still, in effect, a wash. Neither "win" represents a surprise, and neither win results in either campaign with more or fewer votes than they've been counting on.
In fact, Romney will probably take Virginia, too, barring a sudden Obama surge after Monday's final presidential debate.
But once the entire South is in Romney's pocket, things get difficult for him.
If Romney doesn't then take Ohio, he'll need to cobble together 270 votes from the smaller swing states. That means taking Michigan's 16 votes and one of Wisconsin, Nevada, Colorado or Iowa.
Obama's auto industry bailouts are very popular in Michigan, and Democratic Governor Jennifer Granholm is a huge Obama booster.
Without Michigan, Romney could also win with the triple combination of Wisconsin, Colorado and one other state, or lose Wisconsin and sweep every other swing state, but after the union battles earlier this year, a Republican may not be too accepted in Wisconsin.
Romney's best bet may be to reapportion his resources away from Florida to states he's less sure of, like Ohio. But if he makes the move too quickly, he risks letting Obama swoop in and take Florida from him, which would also guarantee Romney's loss.
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