Margaret Coldwell Hassan ( HASS-ən; née Wood; born February 27, 1958) is an American politician and attorney serving as the junior United States senator from New Hampshire since 2017. A member of the Democratic Party, Hassan was the 81st governor of New Hampshire from 2013 to 2017.Born in Boston, Hassan graduated from Brown University and earned a J.D. from the Northeastern University School of Law. After graduating from law school in 1985, she worked at the law firm Palmer & Dodge. She later worked as associate general counsel for Brigham and Women’s Hospital.Hassan first ran for the New Hampshire Senate in 2002 after Democratic Party leaders recruited her. She lost to incumbent Russell Prescott but ran against Prescott again in 2004 and won. Hassan was elected to a total of three two-year terms, representing New Hampshire's 23rd district from January 2005 to December 2010. She became the State Senate majority leader in 2008 before losing reelection in a 2010 rematch with Prescott.Hassan declared her candidacy for governor in October 2011. She defeated former state senator Jacalyn Cilley in the Democratic primary and faced the Republican nominee, attorney Ovide M. Lamontagne, in the general election. Hassan won with 55% of the vote, becoming the state's second female governor. She was reelected in 2014. After becoming governor, Hassan was elected vice chair of the Democratic Governors Association and served as a superdelegate at the Democratic National Convention.In 2016, Hassan ran for the U.S. Senate and narrowly defeated Kelly Ayotte, the Republican incumbent, by about a thousand votes (about 0.1% of the vote). She was reelected in 2022, defeating Republican nominee Don Bolduc. She is serving with Jeanne Shaheen, another former governor. Hassan and Shaheen are the only two women in American history to be elected both governor and U.S. senator.