The 2006 United States Senate election in Rhode Island was held on November 7, 2006. Incumbent Republican Lincoln Chafee sought re-election to a second full term in office, the seat he had held since 1999 when he was appointed to fill the vacancy created by the death of his father John Chafee. He lost to Democratic nominee, former state Attorney General Sheldon Whitehouse by a 7-point margin. Lincoln Chafee later left the Republican Party in September 2007 before running successfully as an Independent for Governor of Rhode Island in 2010.

Lincoln Davenport Chafee is an American politician. He was mayor of Warwick, Rhode Island, from 1993 to 1999, a United States Senator from 1999 to 2007, and the 74th Governor of Rhode Island from 2011 to 2015. He was a member of the Democratic Party from 2013 to 2019; in June 2019, The Boston Globe reported that he had become a registered Libertarian, having previously been a Republican until September 2007 and an independent and then a Democrat in the interim.