Washington, Oct 24 : Former press secretary of George W Bush, Scott McClellan,as backed Democrat Barack Obama to triumph in the race for the White House.
McClellan made his declaration, which had been expected, during the taping of a CNN programme to be broadcast on Saturday.
"From the very beginning I've said I'm going to support the candidate who has the best chance of changing the way Washington works and getting things done," the former White House spokesman told presenter DL Hughley.
"I will be voting for Barack Obama," he said.
McClellan's endorsement comes days after another prominent Republican, former Secretary of State Colin Powell, announced his support for Obama.
McClellan's endorsement, however, lacked the stately tone of Powell's declaration. Appearing on comedian Hughley's first show, he was egged on to say something that would draw attention to the programme.
McClellan came in for fierce criticism from the Bush Administration and the Republican party following the publication in May of his candid memoir "What Happened: Inside the Bush White House and Washington's Culture of Deception."
In the book he admitted to being part of a group within the Bush Administration that deliberately misled the American public in the run up to the Iraq war.
Bush said he was saddened and surprised by the memoir, and the administration and leading Republicans subsequently shunned McClellan.
At the time, he hinted that he might endorse Obama. Saying that he respected Republican nominee John McCain, McClellan told one interviewer: "I also am intrigued by senator Obama's message."