I’ve suggested that this election hinges on Colorado, but the McCain camp reportedly thinks that the Centennial State is a lost cause and that Pennsylvania is its best bet. It’s a risky strategy, and if Obama wins both states (plus likely wins in New Mexico and Iowa), he’ll edge McCain 273-265. But if McCain can pull off an upset in the Keystone State — all other things equal — he’ll trump Obama 286-252.

So how does he pull it off?

Charlie Mathesian, the former Almanac editor and current Politico national editor, has a must-read outlining how McCain could be the first Republican to capture Pennsylvania’s 21 electoral votes since 1988. One of the most important points Charlie touches on is that polls have a tendency to fluctuate wildly in the state and then tighten up in the final days.

Sure, both the Q-Poll and Big Ten Poll released today have Obama leading by double-digits, but The Hill is also reporting that an internal Obama poll shows him in a statistical tie. And while the state has gone blue recently, no Democratic presidential candidate has won more than 51% of the vote here since LBJ in 1964. Even, JFK, Charlie notes, only won by a thin 116,326 out of nearly 6 million cast.

Charlie suggests that the McCain camp thinks it can replicate Hillary Clinton’s successful electoral map from the primary. He quotes Jon Delano, a western Pennsylvania-based political analyst and Carnegie Melon professor, as saying, “What McCain is counting on is that a lot of Democrats who voted once against Barack Obama in the primary will vote against him again.”

One target is the collar counties around Philly. Montgomery County, for example, is the third largest county in the state and one where Hillary beat Obama. Bush Sr. won this county by 22 points in 1988, and McCain is definitely closer to H.W. than W. on style and substance. The McCain camp has also hosted 11 campaign events in the Philly market since the conventions and has spent a whopping $9 million on TV ads here since June.

But the polls still look challenging. A Philadelphia Inquirer survey has Obama up 45-25% in Montgomery County. In neighboring Bucks County, a traditionally Republican-leaning bellwether, the Inquirer has Obama up by 11 points and the Politico has him leading by six.

Outside of the Philly region, McCain will have to turn out the vote big in the “T” section of the state between Philly and Pittsburgh. It’s a very red part of the state – a Northern cousin of Alabama if you ask James Carville. But it’s not as homogenous as some suggest.

The Lehigh Valley is quickly becoming part of the New York Metropolitan area and is trending blue. York and Lancaster Counties in the south-central part of the state are feeling more exurban these days and are trending red. And then there’s Scranton, the poster-child for blue-collar America – which way will it break?

On the other side of the state, McCain will need a huge win in western PA. Obama got demolished out there in the primary, and Democrat John Murtha gone out of his way on two occasions in the past week to suggest that the region is “racist.” I argued back in August that Joe Biden would help Obama in this region, and in Murtha’s district in particular, but I think that Biden will only take him so far.

Look to the Land of the Steagles on Election Night. If McCain looses Colorado, New Mexico and Iowa, but wins the trifecta of Florida, Ohio and Pennsylvania, he’ll be our 44^th president.