On July 25, 2011, Hayden announced that he would run in the October 18, 2011, special election to fill the state senate seat that was vacated by Senator
Linda Berglin, who resigned on August 15, 2011, to take a new job with Hennepin County as a health policy program manager. His candidacy was endorsed by the DFL Party on August 27, 2011. On October 18, 2011, he won the special election with 61 percent of the vote over
Green Party candidate Farheen Hakeem,
Republican candidate Bruce Lundeen, and
Independence Party candidate Matt Brillhart. He was re-elected in 2012. ==Community involvement==