BRISTOL, Pa. — In a packed room at the United Steelworkers Local 88G headquarters, Rep. Patrick Murphy delivered a feisty defense of his voting record and inveighed against the U.S. Chamber of Commerce, China and, most of all, his opponent, former Rep. Mike Fitzpatrick (R).

“We cannot turn back to the failed economic policies” of the Bush administration, the Pennsylvania Democrat said at the rally Friday. “We cannot give them back the keys to the car to allow them to drive our economy back into a ditch.”

While Murphy was received warmly by the sympathetic union hall crowd, Democrats face a daunting enthusiasm gap nationally and are pleading with their supporters to wake up and match the intensity levels coming from Republicans and tea party activists. To help drive up turnout in next month’s midterm elections, President Barack Obama has been stumping at rallies in key states, including one last Sunday in nearby Philadelphia that drew 18,500 people, according to a city estimate.

There was proof here that his effort is working.

“I’m reinvigorated to vote the straight [Democratic] ticket and look forward to doing so,” said Steve Shemin of Bucks County after attending the Obama rally.

But even if Democrats are able to re-energize their base, they are still struggling to attract the independents who played a crucial role in the Democratic waves of 2006 and 2008. According to the latest Gallup poll, independent likely voters favor Republicans over Democrats by 18 points — and that number balloons to 25 points in lower-turnout elections, which midterms often are.

For Democrats to maintain their majorities in the House and Senate, they will need a strong showing in Pennsylvania — where the party made significant Congressional gains over the past four years.

It won’t be easy. The Democrats at the top of the ticket, gubernatorial candidate Dan Onorato and Senate candidate Rep. Joe Sestak, trail in their races. In northwestern Pennsylvania, the Democratic Congressional Campaign Committee this week moved to cut off funding for freshman Rep. Kathy Dahlkemper’s re-election race, an indication they are ceding the contest to Republicans.

In the 8th district, Murphy is in a tough battle in what can be seen as a microcosm of the state’s and the country’s shifting political climates.

Independent voters here, like in many other swing districts that Democrats won in 2006 and 2008, will likely make the difference for Murphy on election night.

“In 2008, I voted for Obama and in the local election for Patrick Murphy. But this time I won’t vote for Patrick Murphy,” said John Ventresca, a construction worker in Doylestown. He said he thinks Democrats focused too long on health care and have not done enough to fix the economy.

The 8th district consists of small slices of Philadelphia and Montgomery counties, as well as all of suburban Bucks County. It’s a swing district — it went for Al Gore for president in 2000 and Sen. John Kerry (D-Mass.) in 2004 while electing a Republican to Congress — but has been trending Democratic in recent years. In 2006, Murphy, an Iraq War veteran, rode the Democratic wave to defeat Fitzpatrick and become the first Democrat elected here in 14 years.

Fitzpatrick, who served just one term in the House, blasts Murphy for voting for all three of the Democrats’ controversial bills: health care, stimulus and cap-and-trade.

“Congressman Murphy has voted 97 percent of the time with Nancy Pelosi, yet he represents a district that demands independence and thoughtfulness from their Representative,” Fitzpatrick said during an interview at a tea party rally in Doylestown, referencing Speaker Nancy Pelosi (D-Calif.). “I think that his judgment day is coming on Nov. 2.”

The only poll publicly released in the district showed Fitzpatrick ahead by
14 points among likely voters.

Mark Nevins, a Democratic consultant for Dover Strategy Group in Philadelphia, said it will be important to see how much cash both campaigns had on hand at the end of September when they file their fundraising reports Friday.

Still, the financial disparity between Murphy and Fitzpatrick isn’t likely to matter much in the final weeks if outside GOP groups decide this is a race that should be a funding priority.

The National Republican Congressional Committee has already spent $189,000 on the race, and American Crossroads and two other Republican-friendly groups are planning to spend
$50 million on competitive races, although they haven’t yet committed to the 8th district. The DCCC has not yet made any independent expenditures on the race.