WASHINGTON -- For weeks, Pennsylvania's Rep. Jason Altmire refused to commit to either side on the health care reform legislation.

The McCandless Democrat is in favor of reforming the system, but he voted against the bill in the House Education and Labor Committee. The bill that Speaker Nancy Pelosi, D-Calif., took to the floor last weekend was more to Mr. Altmire's liking, but he was still worried about cost containment and tax hikes on small businesses.

He heard from advocates and constituents on both sides in town hall meetings and events in his district, then in his Washington office in the final frantic week. He was sought out by the House Democratic leadership and even took a call directly from President Barack Obama, but in the end, he voted against the large-scale overhaul of the health insurance industry.

"My district isn't there," Mr. Altmire said in the wake of the health care bill's narrow House passage Saturday night, 220-215.

Where that district is will determine the second-term Blue Dog's political future. The closely watched health care vote will help define Mr. Altmire's re-election campaign next year, as well as that of his fellow Western Pennsylvania Blue Dog, Rep. Kathy Dahlkemper, a freshman from Erie who voted in favor of the bill. Both hail from districts in which Arizona Republican Sen. John McCain triumphed in his ultimately unsuccessful presidential race last year, and both likely will face stiff GOP competition.

Ms. Dahlkemper was a high-profile figure in the bill's final negotiations. A provision she offered to allow young people to stay on their parents' insurance until age 27 was folded into the bill, and she was a co-sponsor of a successful anti-abortion amendment offered by Rep. Bart Stupak, D-Mich.

Ms. Dahlkemper, a former dietitian, said she was strongly in favor of health reform, and that its abortion language was her only objection to the bill. "Once we were able to pass that amendment, then I was ready to vote for the bill," she said. House colleagues autographed her copy of the 2,000- page bill.

The vote helps her political foes tie her to Ms. Pelosi, an unpopular figure nationally among Republicans and many independents. The National Republican Congressional Campaign Committee had already sent out an image of Ms. Dahlkemper standing with Ms. Pelosi during the merged health care bill's House unveiling last month.

"It's going to help me a great deal," GOP businessman Paul Huber, who is running against Ms. Dahkemper, said of her health care vote. "Those voters are telling me they want common-sense reform in health care. ... People are really concerned about the spending that's going on. This is trillions of dollars, and it's just going to balloon after the first 10 years."

Former Erie County Solicitor John Onorato and Elaine Surma, an agent with the Erie office of the state attorney general, are also potential Republican opponents for Ms. Dahlkemper, who unseated GOP incumbent Phil English in 2008.

The vote also brought Ms. Dahlkemper praise. Americans United for Change and the American Federation of State, County and Municipal Employees launched a $70,000 TV ad campaign thanking her and Pennsylvania's Rep. Chris Carney, D-Susquehanna County, for supporting the legislation. "We want to show them that it's not only the right way to vote, but it's politically popular, too," said Americans United for Change spokeswoman Lauren Weiner.

Liberals have shown their discontent with Mr. Altmire. This week, the advocacy group MoveOn.org launched TV ads critical of him and other Democrats who voted against the bill, and he's been attacked in the progressive blogosphere online.

That's not to say Mr. Altmire is receiving flower arrangements from conservatives these days. GOP attorney Keith Rothfus, who hopes to unseat Mr. Altmire, said he should have taken a stronger stance against the bill. "He never addresses the fact that this is a government takeover," Mr. Rothfus said, citing an argument that a government-run "public option" would gradually expand and muscle out private insurers.

Mr. Altmire has said he is not concerned about the public option as long as it competes on a level playing field with other insurers.

After a premature news media report Saturday said Mr. Altmire would vote in favor of the bill, the NRCC immediately issued a news release saying he "has abandoned his district and handed over his vote to Nancy Pelosi." When that turned out not to be the case, the national Republicans then accused him of being politically expedient.

"For Altmire, this wasn't the vote to stop Washington spending, this was solely a political calculation to protect his career as a politician," said NRCC spokesman Tory Mazzola. "And voters see right through that."

Mr. Altmire has cast himself as a maverick willing to stray from the party line, and he has done so on two major votes this year: health care reform and the climate change bill in June. He votes with Democrats 88 percent of the time, among the lowest rates in the caucus. Ms. Dahlkemper, by contrast, votes with the Democratic leadership at an above-average 94 percent.

She is viewed as more vulnerable by both Democrats and Republicans, though that could change if Mary Beth Buchanan gets into the race against Mr. Altmire, a possibility the Republican former U.S. attorney has been weighing in recent weeks.

Washington correspondent Daniel Malloy writes the "Pittsburgh On The Potomac" blog exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.