Nicola Dickson "Niki" Tsongas (; née Sauvage; born April 26, 1946) is an American politician who served as a U.S. Representative from Massachusetts from 2007 to 2019. She held the seat formerly held by her husband, the late Paul Tsongas, for the district numbered as Massachusetts's 5th congressional district from 2007 to 2013 and as Massachusetts's 3rd congressional district from 2013 to 2019. She is a member of the Democratic Party. In August 2017 Tsongas announced that she would not seek another term in the November 2018 election.