Paul Kirk said it would be an honour to serve as senator
The governor of Massachusetts has named Paul Kirk as a temporary replacement to fill the Senate seat left vacant by the death of Edward Kennedy.
Mr Kirk, 71, is a former Democratic Party chairman and worked for Sen Kennedy for eight years.
The move means that Democrats in the US Senate have regained the majority needed to push through President Obama's healthcare reform agenda.
They fell one seat short through the death of Sen Kennedy.
The Massachusetts state senate voted on Wednesday to allow the state governor to appoint a temporary replacement senator.
Without the change, Sen Kennedy's seat would have stayed vacant until January.
The rule change was one of Edward Kennedy's last wishes.
'Highest honour'
The late senator feared that if his fellow Democrats did not have a full complement of senators, passing a healthcare reform bill would be more difficult.
Mr Kennedy campaigned throughout his career for universal healthcare, and did not want his death to jeopardise prospects for reform.
His widow Vicki Kennedy and son Edward Kennedy Jr had urged Governor Deval Patrick to choose Paul Kirk.
"He (Sen Kennedy) often said that representing the people of Massachusetts in the Senate of the United States was the highest honour that he could possible imagine, and it is certainly nothing that I imagined, but it will be my highest honour, as well," said Mr Kirk.
He is expected to be sworn in on Friday and will serve until 19 January.
Massachusetts Governor Deval Patrick has named former Democratic National Committee Chairman Paul Kirk to temporarily replace the late Edward "Ted" Kennedy in the US Senate.

Ted Kennedy
Kirk, a longtime friend and former aide to Kennedy, is to be sworn in as senator this Friday. He will serve in the post until voters pick a permanent replacement during a special election next January.

The governor told reporters Thursday that matters before Congress and the nation are "too important for us to be one voice short" in Washington.

The appointment gives Democratic leaders in the Senate the 60th seat needed to circumvent efforts by Senate Republicans to prevent crucial votes on a health care reform bill. The late senator had called reform of the nation's health care system the cause of his life.

Kirk said he was honoured to be appointed and added that he will not run in the special election. "He Kennedy often said that representing the people of Massachusetts in the Senate of the United States was the highest honour that he could possibly imagine, and it is certainly nothing that I imagined, but it will be my highest honour, as well," Kirk said.

Kennedy's widow, Victoria, and his two sons, Edward Kennedy, Jr. and US Representative Patrick Kennedy of Rhode Island, both urged Governor Patrick to name Kirk.

The appointment comes one day after the Massachusetts House and Senate passed legislation allowing the governor to name an interim replacement until a special election is held. Kennedy's seat would have remained empty until the next elections, had that legislation not been approved. The rule change was one of Kennedy's last wishes.