Colleagues said Mr Blumenthal lacked objectivity

He used his closeness to Bill Clinton to take a spin through the revolving door between journalism and politics and join the White House communications team in 1997 after writing articles favourable towards President Clinton.

The journalist, who had written for the New Yorker magazine, the Washington Post, New Republic and Vanity Fair, met the Clintons in the 1980s at a Renaissance Weekend. He became close to them while covering the 1992 presidential campaign. He is as close, if not closer, to Hillary Clinton than her husband.

Columnist or Clintonite?

Colleagues criticised him for being too close to the president to write objectively about him. They accused him of urging them to quash negative stories about Bill Clinton.

After Mr Blumenthal was hired as an assistant to the president, the New York Observer wrote, "the long-time cheerleader for Bill Clinton will now get paid by the White House for his boosterism."

Mr Blumenthal defended himself by saying that he was a columnist whose work hinged on his access to the powerful and well-placed.

He adds that he has never been secretive about his liberal leanings. Growing up in Chicago, he became a "runner" for a Democratic precinct captain when he was 12. He went door-to-door to get out the vote.

At the time of his hiring, the administration said Mr Blumenthal would help write major speeches and craft foreign policy. He is also close to Secretary of State Madeleine Albright and UK Prime Minister Tony Blair.

Conservative target

Conservative opponents refer to the former writer as Sid "Vicious" Blumenthal.

In 1996, a year before he joined the White House staff, Republicans accused him of plotting a smear campaign against then presidential nominee Bob Dole. He denied the allegations.

Almost immediately after joining the White House team, he began drawing fire from conservatives. They said he fed the Washington rumour mill with dirt on political opponents.

Conservatives say Sid "Vicious" Blumenthal planted stories about Ken Starr

He took up Hillary Clinton's theme that independent prosecutor Kenneth Starr was part of a "vast right-wing conspiracy" obsessed with bringing down the president.

Mr Blumenthal called Starr "a prosecutor on a mad mission from God" and a "constitutional illiterate."

Republicans believed Mr Blumenthal was responsible for leaking stories about Mr Starr, his staff and Henry Hyde, and they believed Mr Blumenthal was behind the story in Salon magazine about Mr Hyde's extramarital affair 30 years ago. Mr Blumenthal denied the allegations.

Mr Blumenthal found himself one of the three witnesses in the trial against his close friend, Bill Clinton.

House managers decided to include Mr Blumenthal as a witness because they believed he would bolster their case that the president obstructed justice.