At age 84, he beat back a Democratic primary challenge in 2008 and went on to another easy win in the November general election. It made him the first New Jersey person ever elected to five Senate terms.
"People don't give a darn about my age," Lautenberg said. "They know I'm vigorous. They know I've got plenty of energy."
Lautenberg was back in the headlines in December that year — this time as an apparent victim.
After Wall Street money manager Bernard Madoff was accused of running a $50 billion fraud scheme, Lautenberg's family foundation said the bulk of its investments were managed by him. A lawyer for the foundation declined to discuss the amount of any possible losses, but tax records in 2006 indicated Madoff managed more than 90 percent of the foundation's nearly $14 million in assets.
Lautenberg first gained prominence as chairman and CEO of Automatic Data Processing, a New Jersey-based payroll services company he had founded with two friends in 1952. It became one of the largest such companies in the world.
He was first elected to the Senate in 1982, during the presidency of Ronald Reagan. Working his way up the seniority ladder, Lautenberg managed to carve out influence on the environment and transportation, two issues that matter greatly to New Jersey, the nation's most densely populated state.
Before Republicans won control of the Senate in the 1994 elections, Lautenberg was chairman of key subcommittees responsible for transportation appropriations and the Superfund pollution cleanup program. He became the ranking Democrat on those panels after 1994.
From those posts, he worked to secure hundreds of millions of dollars for mass transit projects in the state, which he said would reduce pollution and traffic congestion. He also was a leading defender of Amtrak, the nation's passenger rail system.
In 1984, as a novice lawmaker and member of the minority chamber in the Senate, Lautenberg wrote a bill to withhold federal highway funds from states that did not set 21 as a minimum age to buy and possess alcohol.