2002 United States Senate election in New Jersey

The 2002 United States Senate election in New Jersey was held on November 5, 2002. Former U.S. senator Frank Lautenberg was elected to an open seat over Republican businessman Doug Forrester, after incumbent senator Robert Torricelli dropped out of the race on September 30, facing ethical misconduct allegations, a formal admonishment by the U.S. Senate, and falling poll numbers against Forrester. Primary elections were held on June 4. Torricelli was unopposed for the Democratic nomination, while Forrester won a competitive Republican primary over state senators Diane Allen and John Matheussen. Another leading candidate, Essex County Executive James W. Treffinger, dropped out on April 22 amid a federal criminal investigation for bribery.

In the general election, Torricelli, who was the target of a federal ethics probe, steadily fell behind Forrester in public polling and dropped out in late September. The New Jersey Democratic Party sought to replace him with Frank Lautenberg, who had held the state's other U.S. Senate seat from 1982 to 2001. After Forrester's campaign filed legal proceedings aimed at forcing Torricelli's name to remain on the ballot, the New Jersey Supreme Court ruled that Lautenberg could replace Torricelli.

On election day, Lautenberg defeated Forrester by a 9.9% margin, winning a fourth, non-consecutive term as a U.S. senator. At 78, Lautenberg became the oldest non-incumbent to win a Senate election. Lautenberg became the state's junior senator for the second time when he was sworn in on January 3, 2003. Jon Corzine, who had been elected to Lautenberg's old Senate seat in 2000, became the senior senator, as Lautenberg's previous term in the Senate was not counted for purposes of seniority.