CHARLESTON, W.Va. — After nearly three decades in the U.S. Senate, Democrat Jay Rockefeller of West Virginia said Friday he was ready to retire, calling his unrelenting fight to protect the nation's coal miners one of his proudest achievements.

But in the waning days of his political career, the industry has grown hostile, with coal companies and their conservative allies accusing the five-term senator of being out of touch for defending clean-air regulations and other policies they claim imperil the future of mining.

Rockefeller was also lambasted for support of President Barack Obama's health care overhaul as the president became ever more unpopular in West Virginia.

Rockefeller's retirement puts the seat held by Democrats since 1958 in jeopardy for the party, and well-liked Republican U.S. Rep. Shelley Moore Capito has already vowed to run in 2014.

Though her prospects are uncertain, Capito won a seventh term last fall with about 70 percent of her district's vote, and the state is growing slightly more Republican: The GOP picked up 11 seats last fall in the state Legislature, and two of the three U.S. House seats are now held by Republicans.

At 75, Rockefeller said he wanted to focus on his family and called his decision entirely personal.

"Public service demands and very much deserves nothing less than every single thing that you have to bring to bear," Rockefeller said. "And that's what I have given it. I've been driven to make life better for people here. That's not a slogan for me. It's the truth. And an obsession."

The peak of his career, he said, may have come in 1992, when he threatened to keep the Senate in session over Christmas break if they didn't pass legislation preserving retirement benefits for miners and their families. It passed, he said, and a nationwide strike was averted.

"In that fight, and so many others, I've been proud to stand with the working men and women of America," he said.

"I know the coal companies are going after me," Rockefeller added. "I can live with that, because I know that I am fighting every day for coal miners."

Cecil Roberts, president of the United Mine Workers of America, called Rockefeller "a constant and untiring friend to coal miners and all working people."

Yet Rockefeller's positions in recent years have irritated some people trying to protect the 65,000 mining jobs in one of the country's poorest states.

In a speech on the Senate floor last summer, he chastised coal operators for using divisive scare tactics he said wrongly blame the federal government – and particularly the administration of President Barack Obama – for the challenges they now face.

"The reality is that many who run the coal industry today would rather attack false enemies and deny real problems than find solutions," he said at the time. "Instead of facing the challenges and making tough decisions like men of a different era, they are abrogating their responsibilities to lead."

Those challenges include not only clean-air regulations but also increasing competition from low-priced natural gas, slowing economies and an unchangeable geology that makes the remaining coal seams difficult and more expensive to mine.

Rockefeller supporter Jack Cipoletti, 67, of Charleston, said he appreciated the senator standing up to the industry.

"What could he possibly do to coal that gas hasn't already done?" Cipoletti said. "The `war on coal' is not by him or anyone else. I think the coal industry has fabricated a brand, and the brand is anyone that doesn't agree with them is engaging in the `war on coal.' He didn't pay attention to the slogan. He paid attention to specifics and facts, and if that's the way they want to characterize it, so be it."

Democrats, who hold a 55-45 edge in the Senate, will be defending 20 seats in next year's election while Republicans have 13 seats on the ballot.

No clear Democratic front-runners have emerged for Rockefeller's seat, but the announcement was made earlier enough for the party to find a candidate.

Though Obama is deeply unpopular here, that may not harm Democrats who attempt to succeed Rockefeller. Last fall, Obama lost every single West Virginia county in the general election, but voters still elected Democratic Gov. Earl Ray Tomblin and U.S. Sen. Joe Manchin. They also re-elected longtime Rep. Nick Rahall, D-W.Va., from the southern coalfields.

Democrats outnumber Republicans among registered voters 640,000 to 358,000, according to the Secretary of State's Office. But more than 222,000 people registered with no party affiliation.

Rockefeller, who was hailed for his role in shaping the Children's Health Insurance Program, later took heat from constituents for supporting the Affordable Care Act, Obama's overhaul of the nation's health care system.

He was a top backer of a so-called "public option" allowing the government to sell health insurance in competition with private industry, and pushed the Senate Finance Committee to a showdown vote on such a measure in 2009 – only to see it fail when fellow Democrats opposed it.

As his measure died, Rockefeller called the health insurance industry "rapacious."

"I'm proud of that work," he told The Associated Press in an interview ahead of his formal announcement. People may not like the idea of health care reform now, he said, but "the more it comes into effect, the more they will understand that it's good."

Rockefeller chairs the Senate Committee on Commerce, Science, and Transportation, and previously served at the helms of Intelligence and Veterans' Affairs. In that capacity, he helped persuade the Veterans Affairs Department to revisit disability claims arising from what has become known as "Gulf War Illness."

The great-grandson of famed industrialist John D. Rockefeller first arrived in West Virginia as a volunteer with the VISTA national service program in 1964. Within two years, he had won election to the Legislature, and then as secretary of state in 1968.

After a failed run for governor in 1972 and four years as president of West Virginia Wesleyan College, Rockefeller won his first term as governor. Toward the end of his second term, he narrowly captured the U.S. Senate seat of a retiring Jennings Randolph in 1984.

Rockefeller won by comfortable margins in each of his five terms in the Senate.

"Jay has built an impressive legacy, one that can be found in the children who have better schools, the miners who have safer working conditions, the seniors who have retired with greater dignity, and the new industries that he helped bring to West Virginia," Obama said in a statement.

Rockefeller hails from a family of achievers: In addition to the successes of his oil billionaire great-grandfather, the senator's father, John D. Rockefeller III, was a well-known philanthropist, while his uncle David Rockefeller ran Chase Manhattan Bank.

"There is no Rockefeller left, after Jay, in politics," said Fraser Seitel, a spokesman for David Rockefeller.

____

Smith contributed from Morgantown. Associated Press writers Lawrence Messina in Charleston, and Donna Cassata in Washington also contributed to this report.

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