In 1974 Murtha, then an officer in the Marine Reserves, became the first Vietnam War combat veteran elected to Congress. Ethical questions often shadowed his congressional service, but he was best known for being among Congress' most hawkish Democrats. He wielded considerable clout for two decades as the ranking Democrat on the House subcommittee that oversees Pentagon spending.

Murtha voted in 2002 to authorize President George W. Bush to use military force in Iraq, but his growing frustration over the administration's handling of the war prompted him in November 2005 to call for an immediate withdrawal of U.S. troops.

"The war in Iraq is not going as advertised. It is a flawed policy wrapped in illusion," he said.

Murtha's opposition to the Iraq war rattled Washington, where he enjoyed bipartisan respect for his work on military issues. On Capitol Hill, Murtha was seen as speaking for those in uniform when it came to military matters.

Murtha "was the first Vietnam veteran to serve in Congress, and he was incredibly effective in his service in the House," said Rep. David Obey, a Democrat and chairman of the House Appropriations Committee. "He understood the misery of war. Every person who serves in the military has lost an advocate and a good friend today."

Rep. Ed Markey, D-Mass., said that in part because of Murtha, "America is now on track to removing all combat troops from that country by this summer."

President Barack Obama called Murtha, who was known in his home state for helping bring money and projects to areas depressed by the decline of the coal and steel industries, "a steadfast advocate for the people of Pennsylvania for nearly 40 years" with a "tough-as-nails" reputation.

House Speaker Nancy Pelosi, a staunch supporter of Murtha's in Congress, recalled his service on the battlefield and in Washington. She noted that on Saturday, Murtha became the longest-serving member of Congress from Pennsylvania.

"He is well-recognized as a champion of our national security, always putting the troops and their families first," she said in a statement. "He quietly and regularly visited our men and women serving our country who were injured to assess their needs and offer them thanks and encouragement. As proud Marine, he was always Semper Fi!"

Known for his seriousness, Murtha also had a lighter side. Gov. Ed Rendell recalled Monday that "he was a funny guy, he always enjoyed a good laugh and he was somebody who was a great and loyal friend."

Rendell said Monday that he has not decided when to schedule a special election to replace Murtha. He has 10 days by law; the political parties must come up with their own candidates. The governor said that it would save taxpayer money to hold the election on May 18, the state's planned primary date, but that he might set it sooner in the event of urgent congressional issues.

Murtha was born June 17, 1932. The former newspaper delivery boy left college in 1952 to join the Marines, where he rose through the ranks to become a drill instructor at Parris Island, S.C., and later served in the 2nd Marine Division. He settled in Johnstown, then volunteered for Vietnam, where he served as an intelligence officer and earned a Bronze Star and two Purple Hearts.

He was serving in the Pennsylvania House in Harrisburg when he was elected to Congress in a special election in 1974. In 1990, he retired from the Marine Reserves as a colonel.

"Ever since I was a young boy, I had two goals in life _ I wanted to be a colonel in the Marine Corps and a member of Congress," Murtha wrote in his 2004 book, "From Vietnam to 9/11."

Murtha's criticism of the Iraq war intensified in 2006, when he accused Marines of murdering Iraqi civilians "in cold blood" at Haditha, after one Marine died and two were wounded by a roadside bomb.

Critics said Murtha unfairly held the Marines responsible before an investigation was concluded and fueled enemy retaliation. He said that the war couldn't be won militarily and that such incidents dimmed the prospect for a political solution.

"This is the kind of war you have to win the hearts and minds of the people," Murtha said. "And we're set back every time something like this happens."

Murtha was a perennial target of critics of so-called pay-to-play politics. He routinely drew the attention of ethical watchdogs with off-the-floor activities, from his entanglement in the Abscam corruption probe three decades ago to the more recent scrutiny of the connection between special-interest spending known as earmarks and the raising of cash for campaigns.

Murtha defended the practice of earmarking. The money, he said, benefited his constituents.

Murtha became chairman of the House Appropriations defense subcommittee in 1989.

Murtha's critics recall the Abscam corruption probe, in which the FBI caught him on videotape in a 1980 sting operation turning down a $50,000 bribe offer while holding out the possibility that he might take money in the future.

"We do business for a while, maybe I'll be interested and maybe I won't," Murtha said on the tape.

Six congressmen and one senator were convicted in that case. Murtha was not charged, but the government named him as an unindicted co-conspirator and he testified against two other congressmen.

Murtha's district encompasses all or part of nine counties in southwestern Pennsylvania and embodies the region's stereotypes of coal mines, steel mills and blue-collar values.

State Sen. Don White, an Army veteran and a Republican who represents a portion of Murtha's district, said he and Murtha were longtime friends, despite holding different political views and serving in different branches of the military.

"He made sure that Washington, D.C., knew where Johnstown, Indiana, Kittanning and a lot of other sites in western Pennsylvania were located," White said.

Survivors include his wife of nearly 55 years, Joyce, and three children.