Mr. Warner also was skeptical about President George W. Bush’s 2007 troop buildup in Iraq. But he never broke with the administration to back a fixed deadline for troop withdrawals. That position frustrated Democrats, who had hoped that Mr. Warner would lend his influence to their opposition to the war, and they accused him of not following through on strong talk against the conflict.
Joining with Senator John McCain, who had been a prisoner of war in Vietnam, Mr. Warner thwarted Bush administration efforts to reinterpret the Geneva Convention on the treatment of prisoners in wartime, an approach that the senators said would open captured American military personnel to abuse.
Mr. Warner was not averse to stepping into difficult political situations in the Senate. In 2002, he was among the first to come out against Senator Trent Lott, Republican of Mississippi, after Mr. Lott had made a racially charged comment; Mr. Warner’s stand contributed to Mr. Lott’s decision to step aside as majority leader. He was also a leading member of the so-called Gang of 14, a bipartisan group of senators who struck an independent agreement on judicial nominations in 2005 and averted a fight over the future of the Senate filibuster.
A debonair Virginian, Mr. Warner was sometimes called the senator from central casting; his ramrod military posture, distinguished gray hair and occasionally overblown speaking style fit the Hollywood model.
John William Warner III was born on Feb. 18, 1927, in Washington to John Jr. and Martha (Budd) Warner and attended schools in Washington and Virginia. He left high school at age 17 to join the Navy and serve in the final months of World War II. He graduated from Washington and Lee University in 1949 and enrolled at the University of Virginia Law School before leaving to join the Marines during the Korean War. He returned to law school to obtain his degree in 1953.
Mr. Warner was afterward a law clerk with the United States Court of Appeals for District of Columbia Circuit and then an assistant U.S. attorney in the district from 1956 to 1960. After working in private law practice for most of the 1960s, he was appointed Navy under secretary by President Richard M. Nixon. He became secretary in 1972, serving for two years. He was the federal coordinator of the national bicentennial celebration in 1976.
Mr. Warner endured a reputation as something of a playboy after his first divorce from a member of the wealthy Mellon family, his marriage to Ms. Taylor and a public relationship with the newscaster Barbara Walters. But his long service in the Senate and a record marked by an independent streak ultimately overshadowed much of that image.
He had three children from his first marriage, to Catherine Mellon. His survivors include his wife, Jeanne (Vander Myde) Warner. Complete information on survivors was not immediately available.