Frank R. Lautenberg, who fought the alcohol and tobacco industries and promoted Amtrak as a five-term United States senator from New Jersey, died on Monday in Manhattan. He was 89.

The cause was complications of viral pneumonia, his office said. In 2010, it announced that he had stomach cancer. Though he and his doctors expected a complete recovery, Senator Lautenberg, a Democrat, decided not to seek re-election next year.
His death leaves a vacancy in the Senate that will be filled by Gov. Chris Christie of New Jersey, a Republican. If the governor appoints a Republican, as expected, his party will hold 46 Senate seats while the Democrats’ number will drop to 52. Two independents caucus with the Democrats.
Mr. Lautenberg was the Senate’s oldest member and last surviving veteran of World War II. He had been frequently absent from the Senate in recent months because of failing health but did appear in April in a wheelchair to cast votes in favor of tougher gun-control measures, which were defeated.
First elected in 1982 at age 58 after a successful business career, Mr. Lautenberg served three terms, retired and instantly regretted the decision. When Senator Robert G. Torricelli made a last-minute decision not to seek re-election in 2002, Mr. Lautenberg ran in his place and won the seat. He was re-elected in 2008.
Never a flashy senator — his colleagues Bill Bradley and Mr. Torricelli got more attention — Mr. Lautenberg acquired influence on the Appropriations Committee and had a consistently liberal voting record. Americans for Democratic Action said he had voted liberal 94 percent of the time.
Mr. Lautenberg’s first major victory came in 1984. A freshman senator in the minority party, he pushed through a provision to establish a national drinking age of 21, a measure that threatened to cut 10 percent of a state’s federal highway money if it did not comply. He argued that the change would save lives by ending “a crazy quilt of drinking ages in neighboring states” and prevent those under 21 from driving over “blood borders” to get drunk and then try to drive home.
“He had to fight like hell to get it through,” Jay A. Winsten, associate dean of the Harvard School of Public Health, said in an interview. “The estimates are that the cumulative lives saved are in excess of 25,000.”
Mr. Lautenberg followed that move 16 years later with another condition on highway spending: States must designate 0.08 percent blood alcohol as the level that would constitute being drunk.
In 1989, he led a successful fight to ban smoking on all commercial airline flights. Mr. Lautenberg, once a two-pack-a-day smoker, told the Senate: “With this legislation, nonsmokers, including children and infants, will be free from secondhand smoke. Working flight attendants will avoid a hazard that has jeopardized their health and their jobs.”
He later pursued legislation that prohibited smoking in federal buildings and in all federally financed places that serve children.
Mr. Lautenberg’s other legislative achievements include a 1996 law denying gun ownership to people who have committed domestic violence. He was also the author of legislation requiring that by 2012 all cargo destined for United States ports be screened for nuclear material, a requirement that both the Bush and the Obama administrations said could not be met.
Passenger railroads were another priority of the senator. He won an important victory in 2008 with legislation that nearly doubled Amtrak’s subsidy, and he advocated for federal money to help build another commuter rail tunnel between New Jersey and Manhattan. When Mr. Christie killed the tunnel project in 2011, saying it was too expensive, Mr. Lautenberg, who was a critic of the governor, said the move “will go down as one of the biggest public policy blunders in New Jersey’s history.”
Another Lautenberg measure gave refugee status to people from historically persecuted groups without requiring them to show that they had been singled out. The senator estimated that 350,000 to 400,000 Jews entered the United States under that 1990 law. Evangelical Christians from the former Soviet Union also benefited from the law.