TED KENNEDY is right: Massachusetts needs two voices and two votes in the US Senate.

On Tuesday, the state’s senior senator sent a letter to the legislative leadership and Governor Deval Patrick, asking that they revise the current law to allow for an interim Senate appointment during the special election to fill a vacant seat.

“As I look ahead, I am convinced that enabling the governor to fill a Senate vacancy through an interim appointment followed by a special election would best serve the people of our Commonwealth and country should a vacancy occur,’’ Kennedy wrote.

Gerry Doherty, Kennedy’s longtime friend, says the senator is particularly concerned that the state be fully represented during the upcoming debate about expanding health...