The 75-year-old Democrat's decision comes at a time when his popularity is threatened because of his support for President Barack Obama, who is unpopular in the state, and his willingness to challenge the powerful coal industry, which he said has used divisive and fear-mongering tactics and wrongly blamed the federal government for its problems.
He told The Associated Press ahead of his formal announcement that it was time to retire.
After about three decades in elective office, it was time to "bring more balance to my life after a career that has been so obsessively dominated by politics and public policy and campaigns," he said. "I've gotten way out of whack in terms of the time I should spend with my wife and my children and my grandchildren."
Rockefeller's retirement was widely expected and puts the seat held by Democrats since 1958 in jeopardy for the party. Within weeks of November's elections, Republican U.S. Rep. Shelley Moore Capito vowed to run for the Senate seat in 2014, even if it meant going up against Rockefeller and his storied name. Other Republicans also have been eyeing the seat in recent weeks.
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. Among the vulnerable Senate Democrats are Alaska's Mark Begich, Louisiana's Mary Landrieu and Arkansas' Mark Pryor, all in Republican-leaning states.
Rockefeller's retirement is the first of the 2014 class and comes early in the process, giving Democrats time to find a candidate.
Rockefeller said Capito's announcement did not influence his decision. Willing to devote millions of his personal wealth toward his campaigns—including several against Capito's father, ex-Gov. Arch Moore—the senator said he believes he would have prevailed over the seven-term congresswoman.
In a state that is the second-leading producer of coal, Rockefeller's positions rankled some who are protective of an industry that brings more than 65,000 jobs to one of the nation's poorest states. He accuses mining supporters of a combative closed-mindedness in the face of inexpensive natural gas, concerns over climate change and calls for cleaner ways to burn coal. Mining advocates accuse Rockefeller of abandoning them as Obama ramped up scrutiny of Appalachian mountaintop-removal mining operations.
"I know the coal companies are going after me. ... I can live with that, because I know that I am fighting every day for coal miners," Rockefeller said.
Rockefeller defended his support of Obama and the president's signature health care overhaul, and insisted that their unpopularity with West Virginians did not influence his decision to retire.
"I'm proud of that work," he said.
Rockefeller said the Senate achievement he is most proud of is the 1992 measure aimed at preserving retirement benefits for miners, their widows and children, which he credits for averting a national coal strike. He also has championed stricter coal dust limits in response to a rise in mining-related black lung disease and proposed increased safety measures after the 2010 Upper Big Branch mine disaster killed 29 West Virginians.
Other top issues he has had a hand shaping include child welfare, cybersecurity and foreign trade. He chairs the Senate Committee on Commerce, Science, and Transportation, and previously served at the helms of Intelligence and Veterans' Affairs. He co-sponsored legislation creating the states-level Children's Health Insurance Program, and helped persuade the U.S. Veterans Affairs Department to revisit disability claims arising from what has become known as "Gulf War Illness."
U.S. Rep. Nick Rahall, D-W.Va., was elected to Congress in 1976 as Rockefeller won his first term as governor. He said Rockefeller's sense of humor came out at his first inauguration.
"He told us, 'My name is Rockefeller, but that will not pay our bills,'" Rahall recalled. "He gave us more than his family name. He pledged his heart, mind and strength to us that day. For almost half a century, Sen. Rockefeller's service to his state and its families has never wavered from that commitment."
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. He won by comfortable margins in each of his five terms.
Rockefeller hails from a family of many achievers: In addition to the successes of his oil billionaire great-grandfather, two uncles, Nelson Rockefeller and Winthrop Rockefeller, served as governors of New York and Arkansas, respectively. Rockefeller's father, John D. Rockefeller III, was a well-known philanthropist and founded the Asia Society, while his uncle David Rockefeller ran Chase Manhattan Bank.
"West Virginia has become my life and my cause," Rockefeller said. "I never, ever doubt what it is I'm trying to do. West Virginia provides that to me in the form of fantastically hard-working, tough, warm-hearted people."
Rockefeller became the state's senior senator upon the 2010 death of Robert C. Byrd, a fellow Democrat and the longest-serving member of Congress. In his remaining time in office, he said, he plans to focus now on the fight over federal spending, taxes, the debt limit and the future of Medicaid.
Rockefeller was to be joined during Friday's formal announcement by his wife, Sharon Percy Rockefeller, and other family members. The couple have four children and six grandchildren. Sharon Rockefeller was successfully treated for colorectal cancer after a 2005 diagnosis, and the senator has more recently endured torn tendons in his left knee.
"I will spend the next couple of years thinking of what I can do to continue to fight for the causes I believe in," Rockefeller said. "I will not be leaving West Virginia. West Virginia will always be my home."
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