The 2002 United States Senate election in Iowa was held on November 5, 2002. Incumbent Democratic U.S. Senator Tom Harkin sought re-election to a fourth term in office. Harkin was opposed in the general election by U.S. Congressman Greg Ganske, who fought off a surprisingly difficult challenger in the Republican primary. Though Harkin had narrowly defeated his opponent six years earlier, he was able to defeat Ganske by a fairly comfortable margin to win re-election.