Rep. Jim Gerlach’s (R-Pa.) possible departure from the House to run for governor in 2010 may finally be the opening that Democrats are looking for to pick up his suburban Philadelphia seat.

Democrats have targeted Gerlach since he was first elected in 2002, but the four-term Congressman has survived, even as other Democrats on the ballot in his district win by overwhelming margins.

“It goes without saying that if it’s an open seat, it becomes that much more attractive, knowing that it’s already attractive to begin with,” state Democratic Party Chairman T.J. Rooney said.

Democratic and Republican Pennsylvania operatives say they still have doubts about whether Gerlach will jump into the gubernatorial race, but sources close to him say there is a 75 percent chance that he will run governor next year.

“I’ll believe it when I see that Gerlach runs for governor,” Pennsylvania-based Democratic consultant Larry Ceisler said. “That race just isn’t in the cards for him. I just don’t see how it happens.”

And while the chatter hasn’t been that loud as people weigh how serious Gerlach really is, the possibility that he could vacate his seat still has generated some quiet buzz about who might run instead.

State Rep. Curt Schroder (R) is on often-mentioned Gerlach successor, although he did not return an immediate request for comment on the matter. Sources say Schroder has discussed a bid for Congress with Gerlach, pending whether he runs statewide.

Gerlach’s former chief of staff, Guy Ciarrocchi, said he might also be interested in running for Gerlach’s seat but thinks any discussions are premature. Ciarrocchi lost election to a state House seat in 2008, but his work with Gerlach and as executive director of the Bush-Cheney campaign in 2004 gives him an existing grass-roots and fundraising network.

“I really think it’s premature,” Ciarrocchi said. “I’ve known Jim Gerlach for 20 years, and I think he’ll be the Congressman in this district as long as he wants to be.”

But Ciarrocchi added that if Gerlach runs for governor, he’ll take a bid for his seat into consideration.

Former State Party Chairman Alan Novak is also mentioned as a potential candidate — and has the financial means to boost his own candidacy.

For the Democrats, Rooney said at least one potential candidate had already come forward expressing interest: Businessman Richie Phillips owns a air freight company and has long supported the state party. Phillips is also independently wealthy — a major asset in the 6th district, which lies within the very expensive Philadelphia media market.

In the 2008 cycle, national Democrats struggled to find a quality recruit to run against Gerlach. They eventually settled on businessman Bob Roggio, who lost to Gerlach by a 4-point margin.

Democratic recruiting problems would no doubt change in an open-seat scenario.

“If Congressman Gerlach does in fact run for governor, the challenge won’t be attracting a good-quality Democrat to succeed him,” Rooney said.

Local officials also mention attorney Dan Wofford as a potential candidate to run if Gerlach leaves. The son of former Sen. Harris Wofford (D-Pa.), Dan Wofford narrowly lost an open-seat bid for the seat to Gerlach in 2002.

Sources close to Wofford say he’s looking at running but far from making a decision.

State Sen. Andy Dinniman (D) could also run for the seat, although his office did not return a request for comment on his interest. Finally, attorney Chris Casey, the brother of Sen. Bob Casey (D-Pa.), could also mount a bid for the seat.

An alumni of both chambers of the Pennsylvania General Assembly, Gerlach has long had ambitions to be governor of the Keystone state. He formed an exploratory committee in January, although sources close to him say he will not make a final decision until late June.

“It’s important because Jim wants to make sure a quality candidate is given enough time to hold his Congressional seat,” said a source close to Gerlach.

Gerlach, however, is not alone in his statewide ambitions. Former U.S. Attorney Pat Meehan, former Rep. Pat Toomey and state Attorney General Tom Corbett are also exploring bids, potentially setting up a complicated and crowded primary for Republicans.

Democratic Gov. Ed Rendell is term-limited and will step down from office next year. The Pennsylvania governor’s mansion has switched party hands every eight years for the past 60 years, making the 2010 opening an attractive target for many Republicans in the state.

Gerlach could also be betting on his chances for 2011, when state officials will redraw the lines. The awkwardly shaped 6th district was drawn with Gerlach in mind, but Pennsylvania is expected to lose at least one House seat before the 2012 cycle according to projected census figures.

And because Gerlach is only exploring a bid for governor, the Republican can continue to raise money for his Congressional re-election at a healthy pace in Washington, D.C. If he does decide to run for governor, he will be able to transfer every last dime from his campaign account to his gubernatorial campaign.