CHARLESTON, W.Va. — With West Virginia’s economy battered by a coal industry , Senator of Vermont is hoping that a strong showing in this state’s Democratic primary on Tuesday will keep him a force in the party’s politics by showing that his message still resonates, even though his rival, , has an almost insurmountable lead in delegates.

As Mrs. Clinton and Mr. Sanders have campaigned here in recent weeks, they have found frustrated voters who express the kinds of anxieties heard all across the country — only with a far greater degree of urgency and pain, as they see their communities wither before their eyes.

“We just don’t want to be forgotten,” said Betty Dolin, who co-owns a restaurant in Danville, about 20 miles southwest of Charleston, where customers tucked into hearty meals like meatloaf and country fried steak with gravy.

She pointed out the empty tables that would once have been filled. “We can’t have coal? Bring us something else,” she said. “And I don’t mean job training. A lot of these men are too old to train for another job.”

Presidential primaries tend to bring attention to local issues as candidates move from state to state, and as the candidates have come to West Virginia to campaign, coal has been no exception.

“These communities need help,” Mr. Sanders said last week at a food bank in McDowell County. “It is not the coal miners’ fault in terms of what’s happening in this world.”

In some ways, Mr. Sanders is not a natural candidate to be courting the votes of coal miners: He is outspoken on and advocates moving away from fossil fuels. But his message of economic fairness has been embraced by white, working-class voters.

Mr. Sanders has proposed legislation that would to help coal and other fossil fuel workers and their communities, offering support like financial assistance and job training.

Mrs. Clinton has her own to help coal miners and their communities, including a program to provide funding to local school districts to help make up for lost revenue.

But what people here bring up is a comment she made about coal workers in March, when she said during a televised forum, “We’re going to put a lot of coal miners and coal companies out of business.” She was talking about providing opportunity through clean energy, and she emphasized that coal miners must not be left behind, but the sound bite was a damning one.

When Mrs. Clinton last week, she was met with chants of “Go home!” from protesters. At a round-table event, Bo Copley, a 39-year-old father who had lost his job in the coal industry, told her, “I just want to know how you can say you’re going to put a lot of coal miners out of jobs and then come in here and tell us how you’re going to be our friend.”

Mrs. Clinton called her comment a “misstatement” and expressed regret. But it offended voters in struggling coal communities, and a candidate for West Virginia’s Supreme Court even used it .

“A lot of people that I know are laid off, and you know that had to hurt the people,” said Janet White, 80, a librarian whose husband was a coal miner.

With Donald J. Trump having his two remaining primary opponents last week, the Republican contest here holds little significance, but when Mr. Trump campaigned in West Virginia, he found a receptive audience.

At a rally in Charleston last week, he donned a hard hat given to him by an industry group that had endorsed him, the West Virginia Coal Association, and mimicked shoveling coal. “My hair look O.K.?” he asked after taking the hat off.

Mr. Trump gushed about mining, telling the crowd that he was fascinated by it and promising to revive the industry. “You watch what happens: If I win, we’re going to bring those miners back,” he said. “You’re going to be so proud of your president.” He did not explain how he would go about doing that.

The signs of the state’s economic distress are all over, particularly in areas known for coal production, like Boone County, south of Charleston. In the window of a barbershop and beauty salon in Madison is a yellow sign: “We support coal and those who mine it!”

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But inside, Barbara Bias had no customers. The wives of coal miners used to come in with money to spend, she said. Not anymore.

“Boone County used to be booming, and now there’s nothing,” she said. “This is a ghost town, because when the coal goes out, it hurts all of us.”

In the last quarter of 2011, West Virginia had about 24,700 coal mining jobs; by the last quarter of 2015, that number had fallen to about 14,500, a decline of more than 40 percent, according to an analysis by S&P Global Market Intelligence.

The industry has suffered because of a combination of factors, and a slew of coal companies have filed for bankruptcy protection.

The rise of hydraulic fracturing has caused a boom in production, driving down prices and prompting electric utilities to switch from coal to natural gas. A decade ago, coal was the source of about half of the country’s electricity generation; now, its share is , according to the federal Energy Information Administration.

Tougher environmental regulations have also taken a toll — the Obama administration to cut carbon emissions from coal-fired power plants, and President Obama is deeply unpopular in West Virginia — as has a decline in demand for coal exports.

“It’s a perfect storm of those three factors coming together at about the same time,” said John Deskins, the director of the Bureau of Business and Economic Research at West Virginia University. So far in 2016, coal production in West Virginia is down by more than a third compared with 2015, according to federal data.