WASHINGTON - U.S. Rep. John Murtha, an influential critic of the Iraq War whose congressional career was shadowed by questions about his ethics, died Monday. He was 77. The Pennsylvania Democrat had been suffering complications from gallbladder surgery. He died at Virginia Hospital Center in Arlington, Va., spokesman Matthew Mazonkey said. In 1974 Murtha, then an officer in the Marine Reserves, became the first Vietnam War combat veteran elected to Congress. One of 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 Murtha's 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.