I've mapped out Romney's paths to 270 electoral votes that exclude Ohio. My assumptions are that he wins all states for which Nate Silver gives him a 90% chance or better, and that he loses any state with a 10% chance or less. That gets him to 191 electoral votes and leaves 8 states in play, listed here:
To get 79 more EVs, there are 12 "possible" paths, all of which include FL and NC, and at least two of VA, WI, and CO.
I've put possible in quotes because 11 such paths use Wisconsin, which, at 14%, is ludicrous. That leaves one remaining route, which requires Romney to win every other state on the list. Can he do that? Maybe. Will he? No way.
As always, there's still work to do. So let's do it!