Here's part of why Mitt can pretend "fake momentum" by pretending he's competitive in Pennsylvania. It's next door to Ohio, where all the stops are being pulled out. Ads on Pittsburgh TV probably also go into SE Ohio, giving him a two-fer angle that way, too. The same is probably true in lesser degree of his claims that Minnesota is in play. It's next door to Wisconsin, the western portion of which gets Minneapolis-St. Paul TV. That's the reality. And, northern Iowa, with Iowa also a battleground state, gets TV from Rochester, Minn., in part, I think.
Now, does he have some embers of real momentum? Quite likely. Even Nate Silver won’t say that Romney has zero momentum everywhere.
But, this is the easy way to gin up fake momentum. That’s why Mitt isn’t claiming momentum in Nevada; Idaho and Utah are in the GOP bag, as far as coverage outside of Vegas and Reno within the state. Ditto on Colorado.