Romney surges in Pennsylvania, both sides advertising again [video]

[UPDATED] When the fall campaign season began, the presidential campaign in Pennsylvania was supposed to be competitive, but the U.S. Senate race wasn’t.

In recent weeks, we’ve seen an inversion of sorts in which national Republican leaders gave up on winning the state for the presidential ticket, but GOP Senate candidate Tom Smith came to within striking distance of Democratic incumbent Bob Casey.

A new Franklin & Marshall College poll suggests the Keystone State is reverting to expected form.

The poll shows Romney has pulled to within four points of Obama in the state, 49 to 45 percent.

And it shows Casey, who finally began answering the barrage of TV ads from his opponent, opening up a 10-point lead, 48 to 38 percent.

The tightening of the presidential contest in Pennsylvania is consistent with other independent surveys, and the national trend in the wake of Romney’s performance in the first debate. And Casey’s rebound in the senatorial contest is perhaps to be expected as he finally began competing in the TV ad wars.

Poll director Terry Madonna said Pennsylvania has become “the default state” for the GOP if Romney loses in Ohio, which is hotly contested.

UPDATE: The Obama campaign has responded to the Romney campaign’s return to Pennsylvania by running ads here as well. You can see one of them above.

Obama campaign manager Jim Messina said Monday that “Romney is pretending he’s got a shot in states like Pennsylvania and Minnesota — and we expect Romney or Ryan to visit an out-of-play state this week to pretend they have some momentum there.”

The Democrats have won Pennsylvania in the last five straight presidential elections, leading some analysts, such as the University of Virginia’s Larry Sabato to conclude that it isn’t really a swing state.

But some of those elections have been close, and former Pennsylvania Gov. Ed Rendell said last week a Romney win in the state is a “possibility” if Democratic turnout lags. He said he’d called the Obama campaign and suggested the president visit Philadelphia before the election to fire up the faithful for an Election Day blitz.

Romney and his super PAC have begun advertising in the state, premiering an ad attacking Obama on coal.

You can read the entire Franklin & Marshall poll here.