Robin Rombach, Post-Gazette photos
	U.S. Rep. Melissa Hart runs to a house while campaigning door-to-door in Shaler on Tuesday. A campaign worker found someone home who wanted to talk with the congresswoman
	Jason Altmire talks with supporters while campaigning in New Castle, Lawrence County, at a fund-raiser for Gov. Ed Rendell.

At the start of the new millennium, Melissa Hart seized for Republicans the congressional district north of Pittsburgh that Democrats had long controlled. In two successive races, the energetic conservative showed no sign of giving it up.

Democrats see the 4th Congressional District seat as ripe for retaking, however, through a combination of anti-incumbent sentiment among voters and a capable candidate in Jason Altmire, 38, aggressive, politically moderate and better-funded than his predecessors.

"With all due respect to the candidates who have run against Melissa before, she's never really had a tough race," said political consultant Ron Klink, who lives in the district and represented it in Congress in the 1990s. "I think Jason's an underdog, clearly, but not as much as everybody thought he was going to be, and not as much as previous candidates were."

The race pits two Washington-experienced, relatively young candidates who have to win over the district's many blue-collar voters with socially conservative views. The Democratic registration advantage of 55,000 voters contrasts with increasingly Republican voting tendencies in the district, which includes northern Allegheny County, where both candidates live. It includes some or all of Beaver, Butler, Lawrence and Mercer counties to the west and north and Westmoreland County to the east.

Ms. Hart, 44, who served a portion of the district in the state Senate for 10 years, won her three congressional elections by gaining 59 percent or more of votes over Democrats Terry Van Horne in 2000 and Stevan Drobac in 2002 and 2004. She stands out as Pennsylvania's first Republican congresswoman and a strong voice on conservative issues, generally praising President Bush.

"I think he's probably made some mistakes, but I think everyone does," she told one person in Shaler when door-knocking last week, winning him over with forthrightness, even though he disagreed with her about the president and with some of her staunchest anti-abortion views.

Mr. Altmire used to lobby the congresswoman in Washington as UPMC's vice president for government relations. He lives across the street from her brother in McCandless, and won the Democratic primary over businesswoman Georgia Berner. The race sapped his initial bank balance but built his name recognition in the district. Originally from Lower Burrell, he is in his first race for public office, but he served in the 1990s as a Capitol aide to former U.S. Rep. Pete Peterson, of Florida.

Ms. Hart has sought to use Mr. Altmire's more recent Washington experience as a negative, using "lobbyist" as a disparaging term for him. He contends there was nothing wrong with the job he did for UPMC for seven years after leaving congressional work, but he would be glad for a chance to debate the role of special interests in Washington. Ms. Hart has yet to agree to any of several debate opportunities suggested by groups within the district.

"I feel like we're very close" in the race, said Mr. Altmire, who has been working hard to familiarize himself with the heavy concentration of Democrats in Beaver and Lawrence counties and the Alle-Kiski valley, where his campaign office is based. "People know who Melissa Hart is. They've already made up their mind about her. We just need to let people know who I am."

Part of the enthusiasm held by Democrats throughout the district and in Washington is based on a poll done last month by a firm hired by the Altmire campaign, suggesting he was behind Ms. Hart among likely voters by a 48-44 percent margin. It helped lead the Democratic Congressional Campaign Committee to place the 4th District on a short "emerging races" list of viable challengers to Republican incumbents, which, Mr. Altmire said, has led to financial contributions from national sources.

When asked what she thought of the chances the poll was accurate, Ms. Hart smiled and said, "Zero." She has done her own polling, declining to release details, but said they showed her with a double-digit lead.

"We're talking about issues, not polls," she said. "Sure, he's going to try to spin a story that he's a credible candidate. We're just going to go out and do our job and not worry about him."

The candidates' fund-raising reports through Sept. 30 will be released this week, and the Hart campaign staff says hers will show more than $1 million in the bank, of more than $1.7 million raised overall, with a total goal of $2 million for the race.

That outweighs the $270,000 on hand that Mr. Altmire said he would report, with $600,000 raised overall and a goal of $1 million. He said he didn't have to match the incumbent's funds, but merely raise enough to show he's competitive and to run television ads.

He's been doing that with the help of national figures such as Democratic National Committee Chairman Howard Dean, who visited the district over the summer, and political humorist Al Franken, the featured guest at an Oct. 13 fund-raiser for Mr. Altmire in the Strip District. Ms. Hart was dismissive of such backers of her opponent because they're far more liberal than the district's Democrats.

She began airing ads a week ago focused on her support for the Medicare Part D prescription drug program for senior citizens. Mr. Altmire began TV spot days later, criticizing her on Social Security, veterans benefits and student loan issues.

If the 4th District is like many competitive races in the nation, it ultimately could be determined by how voters, especially Democrats who have developed Republican voting tendencies, feel about the Bush administration's policies and GOP-led House of Representatives. The polls suggesting many Pennsylvania Democrats are in a mood to turn out an even higher-profile Republican incumbent, U.S. Sen. Rick Santorum, help lend optimism to Mr. Altmire.

"If you like the way things are going, vote for Melissa Hart," the challenger tells many people he greets. "If you want some change, vote for me."