Gerlach, who spent a dozen years in Harrisburg before heading to Washington, represents portions of Chester, Berks, Lehigh and Montgomery counties -- an area that was cobbled together back in 2001 by the Pennsylvania General Assembly in order to give a GOP candidate a comfortable advantage.
Yet winning has proved no easy task -- he prevailed by 2 percentage points in both 2002 and 2004 -- and this year, analysts have pegged Gerlach as among the most vulnerable incumbents in the house, if not the most vulnerable.
There's a few reasons why: the unpopularity of President George W. Bush and the war in Iraq, along with the growing number of registered Democrats and the sizable number of independents in the district. Then there's Democratic challenger Murphy; she came so close to defeating Gerlach last time that in this election cycle, she's been able to raise more money, and arguably run a stronger campaign.
"The big issue for the Murphy campaign is to tie Gerlach to the Bush administration," said Robin Kolodny, associate professor of political science at Temple University.
In a recent Keystone Poll, 33 percent of Pennsylvanians said that Bush was doing a good or excellent job.
"If you can convince people that this is somebody who will do what the president wants them to do, you can defeat him," she said.
She countered that for Gerlach -- who's developed a solid reputation for constituent services, and is known as a firm backer of Israel -- the best chance for victory is to mobilize as many registered Republicans as he can to vote on Election Day since the GOP still holds a registration advantage, although it's far narrower than it was five years ago.
Gerlach won Chester County by more than 15,000 votes in 2004. But the fact that in a special election earlier this year residents voted in Andrew Dinniman as their first Democrat to represent the county in Harrisburg since 1990, has led many to speculate that Gerlach might not carry the same margin on his home turf this time around.
"Jim Gerlach is a loyal foot soldier for George W. Bush," said Murphy, an attorney who lives in Lower Merion Township. "He's a supporter of 'stay the course' in Iraq, there's no question. And he hasn't been a leader for ethical reform that is clearly necessary in Congress."
But Gerlach contended that Murphy has offered no alternative plan on Iraq, and argued that he has been unfairly labeled a right-wing Conservative. Despite the fact that he is opposed to abortion -- and takes a hard-line on the issue of immigration reform -- he views himself as a moderate Republican along the lines of Pennsylvania Sen. Arlen Specter.
"I'm right in the middle, on the 50-yard line," said Gerlach. "I'm a moderate centrist representing a very moderate district. And conversely, we think she is pretty far left."
When asked about what aspect of their agenda speaks most directly to the Jewish community, both candidates cited their support for Israel, especially in its recent war against Hezbollah.
Israel actually became a bit of a campaign issue last spring when Gerlach held a town-hall-style event in Lower Merion with Daniel Ayalon, Israel's ambassador to the United States. Ayalon also arranged a separate meeting with Murphy, where they discussed the relationship between Israel and the United States.
If partisan heat sizzled just after Memorial Day, the political temperature is sure to rise further now that Labor Day has passed. Kolodny explained that both campaigns will spend at least $1 million on TV advertising, and that the Republican and Democratic national committees will possibly pitch in twice that much.
"Parties are about winning," she said. "Only 15 seats keep Republicans in the majority."
Meanwhile, just like in the high-profile race for U.S. Senate, Jewish partisans are doing all they can to back both candidates by organizing fundraisers, writing sizable checks and volunteering.
"Lois Murphy absolutely represents the values of our district and of the Jewish community," said State Senator Connie Williams (D-District 175), who is not up for re-election this year, and instead is stumping for Murphy -- whose husband happens to be Jewish -- and other Democrats.
"Our values are the same as most people's values," she continued. "We want safety, we want care for our elders, we want to protect our environment."
Judy Davidson, a Chester County resident who is backing Gerlach and hosting a fundraiser for Republican gubernatorial candidate Lynn Swann, said Gerlach looks out for the interests of the middle class without abandoning the poor. She supports him because of his pledges to make Bush's tax cuts permanent and to fight to abolish, or at least reduce, the estate tax.
"If you start overtaxing, people are going to stop spending," said Davidson. I don't like entitlements. I don't like people who feel entitled to your money."