WASHINGTON (AP) — U.S. Sen. Robert Byrd, a fiery orator versed in the classics and a power broker who steered billions of federal dollars to the state of his Depression-era upbringing, died Monday. He was 92.

A spokesman for the family, Jesse Jacobs, said Byrd died peacefully at about 3 a.m. at Inova Hospital in Fairfax, Va. He had been in the hospital since late last week.

At first Byrd was believed to be suffering from heat exhaustion and dehydration, but other medical conditions developed. He had been in frail health for several years.

Byrd, a Democrat, was the longest-serving senator in history, holding his seat for more than 50 years. He was the Senate’s majority leader for six of those years and was third in the line of succession to the presidency, behind House Speaker Nancy Pelosi.

Sen. Jay Rockefeller, a fellow West Virginian in the Senate, said it was his “greatest privilege” to serve with Byrd.

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“I looked up to him, I fought next to him, and I am deeply saddened that he is gone,” Rockefeller said.

In comportment and style, Byrd often seemed a throwback to the courtly 19th century. He could recite poetry, quote the Bible, discuss the Constitutional Convention and detail the Peloponnesian Wars — and frequently did in Senate debates.

Yet there was nothing courtly about his exercise of power.

Byrd was a master of the Senate’s bewildering rules and longtime chairman of the Senate Appropriations Committee, which controls a third of the $3 trillion federal budget. He was willing to use both to reward friends and punish those he viewed as having slighted him.

“Bob is a living encyclopedia, and legislative graveyards are filled with the bones of those who underestimated him,” former House Speaker Jim Wright, D-Texas, once said in remarks Byrd later displayed in his office.

In 1971, Byrd ousted Sen. Edward Kennedy of Massachusetts as the Democrats’ second in command. He was elected majority leader in 1976 and held the post until Democrats lost control of the Senate four years later. He remained his party’s leader through six years in the minority, then spent another two years as majority leader.

Byrd stepped aside as majority leader in 1989 when Democrats sought a more contemporary spokesman. His consolation price was the chairmanship of the Appropriations Committee, with control over almost limitless federal spending.

Within two years, he surpassed his five-year goal of making sure more than $1 billion in federal funds was sent back to West Virginia, money used to build highways, bridges, buildings and other facilities, some named after him.

In 2006 vote, Byrd won an unprecedented ninth term in the Senate with 64 percent of the vote, just months after surpassing South Carolinian Strom Thurmond’s record as its longest-serving member.

But Byrd also seemed to slow after the death of Erma, his wife of almost 69 years, in 2006. Frail and wistful, he used two canes to walk. By 2009, aides were bringing him to and from the Senate floor in a wheelchair.

Last November he surrendered his chairmanship of the Appropriations Committee.

Byrd’s lodestar was protecting the Constitution; he frequently pulled out a dog-eared copy of it.

Unlike other prominent Senate Democrats who voted to authorize the war in Iraq, Byrd stood firm in opposition.

“The people are becoming more and more aware that we were hoodwinked, that the leaders of this country misrepresented or exaggerated the necessity for invading Iraq,” Byrd said.

He cited Iraq when he endorsed Barack Obama for the Democratic presidential nomination in May 2008, calling Obama “a shining young statesman, who possesses the personal temperament and courage necessary to extricate our country from this costly misadventure.”

Byrd’s accomplishments followed a childhood of poverty in West Virginia, and his success on the national stage came despite a complicated history on racial matters. As a young man, he was briefly a member of the Ku Klux Klan, and he joined an unsuccessful filibuster against the landmark 1964 Civil Rights Act.

He later apologized for both actions, saying intolerance had no place in America.

Byrd briefly sought the Democratic presidential nomination in 1976. But he was a creature of Congress across a career that began in 1952 with his election to the House. He served three terms there before winning his Senate seat in 1958.

Robert Carlyle Byrd was born Nov. 20, 1917, in North Wilkesboro, N.C., as Cornelius Calvin Sale Jr., the youngest of five children.

Before he was 1, his mother died and his father sent him to live with an aunt and uncle, Vlurma and Titus Byrd, who renamed him and moved to the coal-mining town of Stotesbury, W.Va. He didn’t learn his original name until he was 16 and his real birthday until he was 54.

Byrd’s foster father was a miner who frequently changed jobs, and Byrd recalled that the family’s house was “without electricity, … no running water, no telephone, a little wooden outhouse.”

He graduated from high school but could not afford college. Married in 1936 to high school sweetheart Erma Ora James — with whom he had two daughters — he pumped gas, cut meat and during World War II was a shipyard welder.

Returning to meat cutting in West Virginia, he became popular for his fundamentalist Bible lectures. A grand dragon of the Ku Klux Klan suggested he run for office.

He won his first race — for the state’s House of Delegates — in 1946, distinguishing himself by singing and fiddling mountain tunes. His fiddle became a fixture; he later played it on the television show “Hee Haw” and recorded an album.

Byrd was elected to the U.S. House in 1952 in a race in which his brief Klan membership became an issue. He said he joined because of its anti-communism.

Byrd was an early supporter of the Vietnam War, and his 14-hour, 13-minute filibuster against the 1964 civil rights bill remains one of the longest ever. His views gradually moderated, particularly on economic issues.

His love of Senate traditions inspired him to write a four-volume history of the chamber.

Copyright 2010 The Associated Press.