RICHMOND, Va. — Harry F. Byrd Jr., a 20th century champion of racial segregation and fiscal restraint who followed his father into the U.S. Senate but left his father's Democratic Party, died Tuesday. He was 98.

Byrd, whose genteel demeanor masked thundering political clout, was the archetypal Southern senator during his 17 years in Washington. His 1983 retirement amounted to an epilogue for the "Byrd Machine" which once dominated Virginia politics from courthouses to the statehouse.

His death was first reported by The Winchester Star, where his son, Tom Byrd, is president and publisher. There was no word on the cause of death.

When failing health forced his father, Harry F. Byrd Sr., to vacate his Senate seat in 1965, the namesake son easily won a special election the next year to serve out his term. Then he left the still-dominant Democratic organization, marking only the second time an independent candidate had won a U.S. Senate seat. He won re-election in 1970 and 1976, winning more votes than his Democratic and Republican opponents combined.

"It's a hard way to run, but if you can win that way it's the best way to win," Byrd later said. "You're totally free of obligations to anybody. ... You don't have to follow a party line."

From the 1920s through the 1960s, almost all Virginia public policy carried the Byrd imprimatur, from its debt-averse "pay-as-you-go" approach to government finance to defiance of the 1954 U.S. Supreme Court decision that struck down racially segregated public schools. In 1956, Byrd denounced the ruling as an "unwarranted usurpation of power" by the high court.

He said he "personally hated" to see schools close, but defended Virginia's "massive resistance" to federal desegregation orders, claiming it helped the state avert racial violence.

"It is one thing to sit here in 1982 and say what was done in 1954 was a mistake," he said in a 1982 Washington Post interview. "It may or may not have been, because you have to look at it in the context of the times. When you have to make a very dramatic change, sometimes, most times, that needs to be done maybe over a period of time and not abruptly."

Byrd, like his father, preached fiscal discipline and claimed Congress could balance the budget if it would just hold annual spending increases under 5 percent.

In 1982, his final year in the Senate, Byrd said he was leaving public service with his convictions and integrity intact, but regretting that "Congress refuses to obey its own law which mandates a balanced budget."

Byrd's break from the Democratic Party held enormous symbolic and cultural significance, an ominous sign of the party's imminent tumble from dominance and a polar shift in Southern politics.

"In Virginia, it helped bring conservatives from the Democratic Party into the Republican Party. Byrd first helped them stop voting Democrat. It was a half-step," said Larry J. Sabato, director of the University of Virginia Center for Politics.

Lyndon Johnson carried Virginia in 1964, but it was the last Democratic presidential victory there for 44 years, until Barack Obama in 2008. Richard Nixon's 1968 "Southern Strategy" brought conservative Byrd Democrats over to the GOP, and they've never gone back.

Byrd said his departure wasn't about ideology but about a party edict that all Democratic candidates sign an oath to support the party's ever more liberal national tickets. One colleague said Byrd also felt he could accomplish more without partisan encumbrances.

"He had a remarkable capability of being able to reach across the aisle," Republican former Sen. John W. Warner said after learning of Byrd's death. Warner, 86, won the first of his five terms in 1978 and represented Virginia alongside Byrd for four years.

Byrd was old school, even in the time of old school, Warner said. Recalling an underground tramway that links the Senate office building to the rest of the chambers, Warner said, "Harry told me one day, 'You won't see me on that. I want to walk. Exercise is good.'"

Byrd was born in Winchester on Dec. 20, 1914, into a venerable Virginia name. His uncle was Adm. Richard Byrd, the first aviator to fly over the North Pole and the South Pole.

At age 10, traveling with his father as he campaigned for governor, he was the elder Byrd's unwitting sounding board as his father would "think out loud."

"I didn't always know what he was talking about, but it got me interested in politics," he said.

He graduated from Virginia Military Institute and the University of Virginia, served in the Navy in World War II and won a state Senate seat in 1947.

Byrd remained engaged and informed about Virginia public affairs after leaving elective politics through his family's newspapers, said Virginia Supreme Court Justice William C. Mims.

Mims said he was surprised by Byrd's advice before a momentous 2004 vote on a bitterly contested budget-balancing tax increase advanced by then-Gov. Mark R. Warner, a Democrat and now Virginia's senior senator.

"His view was that a tax increase was the last thing that should be considered, but that the responsible position was to, in fact, to consider it, and under those circumstances, he would vote for it," Mims said.