A traveler wishing to ride the rails in Amtrak’s Northeast Corridor between Washington, D.C., and Boston can choose from dozens of trains per day. Anyone wishing to ride the Sunset Limited from New Orleans to Los Angeles, however, has more limited options: There’s one train on Monday, one on Wednesday and one on Saturday.

Some 3.3 million people took the Acela express in the Northeast Corridor in fiscal 2013, and 8 million people used the regular Northeast Regional service. But fewer than 103,000 people signed up for all or part of the 48-hour trip on the Sunset Limited, which crosses the entire expanse of Texas and then snakes along the southwestern border to California.

That, in a nutshell, is Amtrak’s blessing and its curse. Amtrak operates a hugely popular and profitable 453-mile link between major Northeastern cities. But it also maintains sporadic and money-losing service that takes days to make a trip across desolate desert that would only take a few hours on a plane.

That dichotomy has bedeviled Amtrak and its overseers in Congress. How do you keep up with the investment in the Northeast Corridor while maintaining a national network?

Last week, the House Transportation and Infrastructure Committee nudged Amtrak toward beefing up the Northeast Corridor while reducing the losses on the other lines. The bill suggests lawmakers want to prioritize the Northeast service while putting pressure on the rest of the system to shape up or face the consequences.

But lawmakers have been reluctant to spell out what exactly those consequences might be.

The bill would reinvest the profits from the Northeast Corridor routes back into the line to address the backlog in capital projects that have built up there. Elsewhere, it would require an independent evaluation of the passenger rail system’s 15 long-distance routes to find places to cut costs. It also would open the door to private sector competition along those routes.

Further, the House bill would reduce Amtrak’s authorized spending levels by 40 percent, to bring them in line with the spending that has actually been appropriated by Congress. In essence, the move indicates Congress is not likely to significantly bulk up its investment in passenger rail anytime soon.

The bill follows Amtrak’s move last year to divide its system into three “lines of business.”

One serves the Northeast. Another comprises routes up to 750 miles long where state governments make up operating shortfalls. The third brings together the remaining long-distance routes that cross state lines which eat up the most in federal subsidies. Under the House bill, each line of business would be funded separately, allowing profits from the Northeast line to stay there.

The Golden Child

This fiscal year, Amtrak expects to post a $290 million operating profit from its Northeast Corridor line. The state-supported lines, however, are expected to lose $83 million and the long-distance lines are expected to lose $618 million.

Numbers like those have made the Northeast line the golden child in lawmakers’ eyes.

“We want to make sure that we’re able to keep money on the Northeast Corridor to create greater investment in our infrastructure,” said Rep. Jeff Denham, R-Calif., chairman of the Transportation subcommittee on railroads. “There’s a lot of passengers there and they deserve to have a more efficient rail system.”

Rep. John L. Mica, R-Fla., a former chairman of the full committee, said there’s no interest in getting rid of Amtrak service. Still, he added, “some of this waste, inefficiencies and losses have to be cut.”

“What they need to do is look at the service. Some of the service needs to be bid out,” Mica said, singling out the system’s food service. “There are opportunities to actually expand service and employment, but Amtrak is still a Soviet-style operation and they couldn’t put a two-car train funeral together.”

Democrats have largely held their fire, noting the bill stopped short of abolishing the long-distance lines, as rail advocates had feared.

Rep. Peter A. DeFazio, D-Ore., who serves on the rail subcommittee, said the bill was “better than I would have expected.”

“There’s no cutbacks in the long-distance support or authorization in the bill,” he said. Still, he added, “From a Westerner’s perspective there’s too much emphasis on the Northeast Corridor.”

Rep. Corrine Brown of Florida, the ranking Democrat on the subcommittee, also supports the bill, allowing the committee to tout the measure as a bipartisan achievement.

Amtrak said in a statement it wanted to work with Congress “to enact a bill that addresses critical infrastructure investment needs, improves safety and security, enhances customer service and provides for greater financial efficiencies.”

‘Debate Has to Happen’

Still, it’s clear the reauthorization proposal sets the stage for what may be drastic changes in the way the country’s passenger rail system looks. While this week’s bill may be a relatively modest move, it nevertheless brings renewed attention to the system’s difficult financial position, one that Congress is not about to remedy anytime soon.

“There is a very clear debate that has to happen,” said Adie Tomer, an associate fellow at the Brookings Metropolitan Policy Program. “Do we want a system that has broad national coverage and what economists call geographical equity that gives more people service but will come at continuous financial losses ad infinitum? Or do we want to limit those services, create more operating efficiencies but lose some of the social benefits we get from running those geographically equitable routes?”

While the House bill sets that conversation in motion, it sidesteps the most difficult question about the fate of long-distance lines.

“It’s a legislative version of kicking the can down the road,” said Sean Jeans-Gail, vice president of the National Association of Railroad Passengers. “What they do is they say we’re going to cut Amtrak authorization by 40 percent, we’ll be authorizing Amtrak at current levels, and then we’re going to just hope that the private sector comes in on its white horse and saves us from having to do the dirty work of having to identify revenue.”

But finding ways to reduce the losses on the long-distance routes, though it may make financial sense, will be a political challenge.

Amtrak trains serve more than 500 communities in 46 states. In some of them, the train is one of the few connections to the outside world. Pulling back from those places could jeopardize the support of some senators, particularly Republicans from rural areas. That could make it very difficult to enact an overhaul.

For now, no one expects the House bill to head to the president’s desk anytime soon. With barely five weeks left this session, Congress will have more pressing issues to tackle. But the bill serves as a marker for a broader push in the next Congress when Republicans could find themselves controlling both sides of the Capitol. If that’s the case, they will have to figure out how hard they want to push Amtrak toward financial sustainability.

And while rail advocates are generally relieved that the bill does not call for outright service cuts, they’ve also made clear they’re not about to stop pushing for more government investment.

“We’d like to see a little more growth in the program,” said Robert Healy, vice president for government affairs at the American Public Transportation Association. “It’s nice that the Congress is looking at intercity passenger rail and they recognize it can play an important role.”