Sen. John Kerry says he supports U.S. Rep. Edward Markey's decision to run for the U.S. Senate seat that would become vacant if Kerry is confirmed as Secretary of State.

Markey, the dean of the state's congressional delegation, also picked up support Friday from Victoria Kennedy, the widow of the late U.S. Sen. Edward Kennedy.

Though he stopped short of formally endorsing Markey, Kerry said in a statement that the Malden Democrat was "one of the most experienced and capable legislators in the entire Congress." He also said Markey would be able to "hit the ground running" if he joined the Senate.

Meanwhile, U.S. Rep. Niki Tsongas, who had also been mentioned as a possible Democratic candidate in the special Senate election, announced she won't run and will continue serving in the House.