Nate Silver's final forecast is delightfully brutal: 315-223 EV, Obama; 51%-48% popular vote, Obama; 92 percent chance of winning one way or another, Obama.
Perhaps the best news is that should calling Ohio tonight be delayed Florida-style because its secretary state, who's in charge of voting, doesn't believe in voting, Obama's expanding cushion elsewhere could render its 18 EV moot. Let's say it's midnight and Ohio's returns remain in doubt for whatever inexcusable reason; Obama could instantly compensate with a win in Virginia, plus Iowa or Colorado. Or he could lose Virginia but by winning Iowa, Colorado and New Hampshire still exceed 270 EV (since Pennsylvania, Wisconsin and Nevada are safe).
Silver's forecast, Sam Wang's forecast (332-206 EV, Obama), virtually every forecast outside the ravings of Dick Morris & Friends can explain the how of Obama's imminent victory, but not the why. As Silver wrote in this morning's wee hours: "Whether because of Hurricane Sandy, the relatively good economic news of late, or other factors, Mr. Obama appears to have gained ground in the closing days of the race." In other words, it's anyone's guess.
Mine, I would tend to dismiss recent economic news. Neither good nor bad developments in the economy have seemed to empirically register much of a consequence throughout the campaign. Hurricane Sandy? Could be, yet Obama's polling numbers began upticking prior to Sandy, so again, I'd tend to dismiss its electoral effect.
That leaves "other factors," among which I'd rest on two. As we moved farther in time away from the commentariat's oddly prolonged obsession with Obama's first debate performance, the latter's importance as a deciding factor receded in the electoral mind, which then gradually trended back to its original state. Second, Romney's last-ditch, utterly desperate and soundly despicable Ohio Jeep-ad lie was, finally, one Big Lie too many. Appalled reaction to the ad bled over Ohio's boundaries and into less secure Obama states, such as Virginia and Colorado--all of which now portend a rather sizable EV victory for President Obama.