According to the Seventeenth Amendment to the United States Constitution adopted in 1913, U.S. senators are popularly elected for a six-year term.
Before 1914, and the enforcement of the Seventeenth Amendment, the state's U.S. senators were chosen by the Massachusetts General Court, and before 1935, their terms began March 4.
In 2004, the Democratic-controlled state legislature changed the vacancy-filling process, mandating that a special election occur, which removed the governor's appointment power.
[5] While terminally ill with brain cancer, Ted Kennedy requested that the Massachusetts legislature change the law to allow an interim appointment.
[6] On September 24, 2009, Governor Deval Patrick signed the bill, and appointed Paul G. Kirk, who had previously served as one of Kennedy's congressional aides and as chairman of the Democratic National Committee.