Mo Cowan[a] Democratic Ed Markey Democratic The 2013 United States Senate special election in Massachusetts was held on June 25, 2013, in order to fill the Massachusetts Class 2 United States Senate seat for the remainder of the term ending January 3, 2015.

The vacancy that prompted the special election was created by the resignation of Senator John Kerry, in order to become U.S. Secretary of State.

The race drew remarks from the media, because of its potential similarity to the 2010 special election, when Republican state senator Scott Brown upset the Democratic nominee, Massachusetts Attorney General Martha Coakley.

[6] The incumbent senator, John Kerry (Democratic), was nominated to serve as U.S. Secretary of State by President Barack Obama on December 21, 2012.

[12] Patrick's former chief of staff, Mo Cowan, was appointed to replace Kerry in the Senate on the same day, and immediately ruled himself out of the special election.