Rep. Jim Gerlach (R-Pa.) is vulnerable in 2008.

His three narrow victories, the political makeup of the suburban Philadelphia 6th district, and Democrats in Pennsylvania and Washington, D.C., all make that very clear — except that six months after Gerlach survived one of the biggest political waves in a generation, potential Democratic challengers keep saying “no” to taking him on.

“There are no elected officials who want to make the run,” said Democratic consultant Larry Ceisler, who is based in Philadelphia. “He’s had three difficult races he’s come out of, and I think people know he’s going to be very difficult to beat.”

State Sen. Andrew Dinniman (D) is giving mild consideration to running but said he has not yet returned phone calls from Democrats in Washington, D.C., who want to discuss the race with him.

Dinniman, who won a special election last May after 14 years as a Chester County commissioner, was the first Democrat elected to his state Senate seat in more than 100 years — which is why some Pennsylvania Democrats believe he would be a formidable challenger to Gerlach. But Dinniman said he would determine his 2008 plans over the summer, after the Pennsylvania state budget is put to bed.

“If you call me in July or August I can give you a more definitive answer,” Dinniman said Friday.

Meanwhile, Philadelphia attorney Robert Fox already has told Democratic recruiters no, and he confirmed as much in a brief telephone interview on Friday.

By the numbers, Gerlach appears eminently beatable.

He won a third term in November with 51 percent of the vote, equaling the percentage of his two previous victories, while the Democratic presidential nominee won the district in 2000 and 2004 — albeit closely. And Pennsylvania’s leftward lurch in the previous cycle suggests the Democrats could be on track to win the district again in the 2008 presidential contest.

But Gerlach, a moderate Republican, has a reputation for working hard, both on official Congressional business, constituent services, and on the campaign trail. He makes frequent appearances in his district, and operatives familiar with the district add that he employs a talented staff.

The Congressman also has been successful at raising money, although he managed to beat attorney Lois Murphy (D) last year despite being outspent $4 million to $3.4 million. Gerlach raised $212,975 in the first quarter of this year, to close the period with $107,000 in cash on hand.

“If I was the [Democratic Congressional Campaign Committee] I’d save my money and spend it elsewhere because this guy has taken to two body blows and stayed in the ring,” said one Republican operative who is familiar with the district.

This Republican said Gerlach benefited considerably from his two tough races against Murphy — she lost to him for the first time in 2004. The Congressman campaigned hard and advertised extensively in those races and in the process was able to define himself on his terms and achieve a reasonably high name recognition.

For these reasons, Gerlach’s eventual 2008 Democratic challenger could find it difficult to redefine him, the GOP operative said.

Democrats disagree, and they remain confident that they can pick off Gerlach. They maintain he is out of step with the district and ripe to be ousted, particularly in a presidential year.

“He is vulnerable and Democrats will have a strong candidate to run against him in 2008,” DCCC spokeswoman Carrie James said.

But thus far, Democrats are at a loss for candidates to challenge him. James insisted Democrats have viable candidates in the offing but declined to provide their names.

A few political operatives based in Pennsylvania who were interviewed for this story also were at a loss to name viable, prospective candidates interested in taking on Gerlach, in large part because Democrats already in elected office — like Dinniman — don’t appear to be in a rush to take on such a fight.

“I have not heard of any names surfacing in the 6th,” said one well-placed Democratic operative in Pennsylvania. “It’s a tough district.”

Gerlach campaign spokesman Mark Campbell said whomever the Congressman faces in 2008 is immaterial, because he’ll work hard and bring the same high intensity to the campaign regardless of his opponent.

Dinniman, in winning what had been a Republican state Senate seat by 12 points, captured 97 percent of the Democratic vote in that election while garnering more than 40 percent of the GOP vote. But Campbell was unimpressed, saying that state Senate races are a far cry from a heated Congressional contest.

“There’s a big difference between winning a state Senate seat and winning a Congressional seat,” Campbell said, adding: “We know the Democrats will file someone, and Jim will run a very, very hard campaign.”

Other than a portion of blue-collar Reading, the 6th district is populated by mostly affluent liberal Republicans and liberal Democrats. Dinniman said Democrats would do well to recruit a candidate out of Chester County or Berks County.

He said doing so would eliminate Gerlach’s hometown advantage and likely produce a candidate who appeals to the liberals who increasingly populate the part of the district nearest to Philadelphia, while simultaneously attracting votes from conservative Democrats who live in the western part of the district and tend to vote Republican.

Dinniman predicted that formidable challengers would come forward to take on Gerlach and said he doubted his three consecutive tough victories were scaring anyone away.

“The election was only six or seven months ago. People need a breather to reassess,” Dinniman said.

National Republican Congressional Committee spokeswoman Julie Shutley said targeting the 6th district would be fruitless for the Democrats.

The NRCC has prioritized winning back the 4th district in western Pennsylvania and the 10th district in the northeastern part of the state — and might target other Keystone State seats.

“The Democrats should watch out for their potential one-and-dones in Pennsylvania instead of wasting their time in Pennsylvania 6,” Shutley said. “If they couldn’t beat Gerlach last year with the wind at their backs, they certainly aren’t going to come close in ’08.”