JOHNSTOWN, Pa. — This is the town that Jack built, earmark by earmark, into an oasis of economic development projects for 36 years.

But Tuesday could mark the end of the late Rep. John Murtha’s (D) empire.

His top aide — Rep. Mark Critz (D) — has carried the 12th district torch for the past two years since Murtha’s death. But last year, Republican mapmakers reconfigured the district, forcing Critz into an uphill battle against fellow Democratic Rep. Jason Altmire in the gritty former steel towns surrounding Pittsburgh.

“I don’t know a whole lot about Critz, except what I’ve seen on TV,” said Doug Fehr, a 62-year-old Democrat some 75 miles across the district in Altmire’s base of ritzy McCandless. “I do know that he took the Murtha seat. In that area, I think it’s a good thing. But I don’t think it means much out here.”

The geography of the new district favors Altmire, with about 66 percent of Democratic primary voters coming from his current turf. But polls show Critz closing the gap in the final days before Tuesday’s primary, and now both candidates have turned to focus on their respective bases.

In Johnstown, Critz’s defeat would mean the end of the Murtha legacy and the demise of the enterprise commonly known on Capitol Hill as “Murtha Inc.” On the flip side, his victory would signal that organized labor still carries political weight in the region after decades of decline.

“There was also Jack Murtha, and that guy who was with him. That was me,” Critz recalled in an interview last week. “My name was, ‘Oh, you’re Murtha’s guy.’ So when I started campaigning two years ago, people were saying, ‘Oh, you’re Murtha’s guy.’ Well, my name is actually Mark Critz, but, yeah, I’m Murtha’s guy.”

Altmire is also aware of the mantle — or the burden — that being Johnstown’s Congressman brings.

“Johnstown has not had a Member of Congress that has not lived in Johnstown since World War II,” Altmire said. “I don’t want them to look at me and say, ‘That’s the guy who knocked out our Congressman.’ I do approach that always in the front of my mind, of trying to make a first impression.”

Yet Altmire’s most recent TV spot refers to Critz as “Johnstown Congressman” — a dig at his colleague intended to energize Altmire’s base.

Since Murtha’s death in early 2010, there have been significant changes for Johnstown. For one, Members don’t earmark funds anymore like the Pennsylvania power player did for decades.

The late Congressman’s name appears on dozens of buildings in the Johnstown area, from the John P. Murtha Regional Cancer Center to the John Murtha Johnstown-Cambria County Airport. The lawmaker ushered to town many more projects that don’t bear his name, such as the weapons factory at Nammo Talley Defense.

In a rented warehouse space surrounded by green pastures, dozens of workers construct an over-the-shoulder, disposable firing mechanism, the M72 LAW, to be sold for $2,000 apiece to the Marines. Critz, in an olive suit, studies the production stations as he tours the factory before greeting the employees over delivery pizza.

He’s still uncomfortably self-aware of his role as an elected official. Critz refers to the Congressional pin as a “button” in his southwestern Pennsylvania twang and remarks out loud about his post-pizza heartburn.

“As a Member, your jokes are funnier, you’re more interesting and you’re much more handsome,” Critz told the employees last Wednesday. “In 13 days and eight hours, we’ll find out if I get to keep doing it.”

Later that day, Critz greeted United Steelworkers members during the shift-change at the Gamesa wind turbine plant in Ebensburg — another project attracted to the district by Murtha’s Appropriations Committee clout. Now the workers play a part in Critz’s campaign strategy to drive out his union base for the primary.

But Critz doesn’t even mention he’s running for Congress to the workers rushing through the doors in their Carhartt jeans. As they pass him carrying their Igloo lunch coolers, he utters an understated introduction, “Mark Critz, nice to meet ya.”

These are the types of voters who will keep Critz in office — if they turn out next week.

“He’s Democratic and he also carries the legacy — the torch — for the late John Murtha,” said Michael Katchmer, a 47-year-old USW member and Critz supporter, as he left the plant.

Many local unions made rare endorsements in a Member-vs.-Member race by backing Critz. Some of the same unions supported Altmire in his 2006 and 2008 campaigns but turned on him after his vote against the president’s health care law.

“There are some in the national leadership of unions and some local union leaders who are unhappy with me over the health care vote, and they’ve made that clear,” Altmire said in an interview at his Lower Burrell campaign office. “But I don’t believe that’s going to carry through to all union families in the district.”

Labor unions do not boast the membership they used to in Steel Country. There are about 30,000 union members who are registered Democrats  in the 12th district, according to Tim Waters, the political director for the United SteelWorkers.

When Murtha came to Congress in 1974 — in the prime of Western Pennsylvania’s steel-producing years — the same union had about 150,000 members. Ruth Villa, a retired Democrat and former Murtha volunteer, recalled how the late Congressman would rise early in the morning to greet steelworkers when they arrived at work.

“They can’t [now] because the numbers aren’t there,” Villa, 88, said. “Mr. Murtha went to the mill gates at five in the morning. And I feel strongly, if the mills were still there, Mark would be there.”

The primary here serves as a test of organized labor’s remaining strength in the region. If steel unions can’t turn out voters to elect one of their own, then what kind of political boost do they offer?

“Altmire’s got huge name recognition and more money, and he was 30 points ahead,” said Waters, a Critz supporter. “The fact that it’s even close is a tribute to Mark’s message and his position. If we pull this out, it will be the biggest upset in the history of the House of Representatives in 20 years.”

Labor’s 40-year decline is widespread across the district. In Altmire territory in Beaver Falls, Douglas Stopp looked out over the vacant brown lots and decrepit tubular steel factories where he worked decades ago.

“It was a very powerful union at that time,” he recalled. “Politically, they were very strong. But today, they just don’t have the membership.”

A few minutes earlier, Altmire met with constituents in the basement at St. Philomena Community Hall. The lanky former high school football star proclaimed the economy is on the upswing in southwestern Pennsylvania. It’s a tough argument to make.

“I don’t see economic growth here in Beaver Falls. I see desperation,” Mary Bentley, a 47-year-old undecided Democrat, told Altmire. “I tell all my three children to run as far away as they can from Western Pennsylvania.”

Altmire’s argument played better the next day at a golf club Rotary Meeting in the wealthy Pittsburgh suburb of McCandless, where the Congressman reiterated that he’s “bullish” about the region’s economic prospects.

The redrawn 12th district crosses all income levels, joined together by Altmire’s  middle-class hometown of Lower Burrell — current Critz territory.  

Lower Burrell Mayor Donald Kinosz remembers Murtha. They shared space in the municipal building for years, but now he’s ready for Altmire to succeed.

The Congressman “could be to Lower Burrell what Murtha was to Johnstown,” Kinosz, 71, said. “Drive through Johnstown and you’ll see ‘Murtha, Murtha, Murtha.’ Maybe someday we’ll see, ‘Altmire, Altmire, Altmire’ here.”