The longest-serving member of the US Senate has backed Barack Obama’s bid for the White House.

Robert Byrd has represented West Virginia since 1959.

During his turbulent career in the Senate he has admitted, and frequently apologised for, membership of the Ku Klux Klan as a younger man.

A controversial figure, he also attempted to wreck the Civil Rights Act 1964 and the Voting Rights Act 1965, which he has also said he regrets.

His endorsement of the 46-year-old Senator from Illinois is a significant boost to the young Democrat.

Just last week Senator Hillary Clinton, his opponent for the party’s nomination for President of the United States, was proclaiming her victory in the West Virginia primary as a reason for her to continue to run.

Senator Byrd, 90, was effusive in his praise for Senator Obama, calling him “a noble-hearted patriot and humble Christian.”

As President pro tempore of the Senate Senator Byrd is third in the line of Presidential succession after the Vice President and the Speaker of the House of Representatives.

He told reporters that he did not involve himself in the campaign while the West Virginia primary was being held, “but the stakes this November could not be higher.”

“As people all across this great nation know, I have been one of the most outspoken opponents of the Bush administration’s misguided war in Iraq and its sabre rattling around the globe.

“Barack Obama is a noble-hearted patriot and humble Christian, and he has my full faith and support.”

The veteran Senator praised both candidates’ “integrity, honour, love for this country and strong belief in our Constitution.”

Despite a big win in West Virginia, Senator Clinton’s chances of winning are slim.

Senator Obama leads in the number of pledged delegates at the party convention in August, and there is a strong sentiment that he has already become the presumptive nominee.

Senator Clinton has vowed to fight on in the few remaining caucus and primary races.

Senator John McCain has already become the presumptive nominee for the Republican Party.

Americans will elect a new President on November 4th and he or she will take office on January 20th 2009.