Oprah's Star Appeal Boosts Obama Campaign

Oprah Winfrey, who has already used her celebrity power to raise millions for Barack Obama, is stepping up her support for the Democratic presidential candidate by vowing to begin campaigning for her "favorite guy".

Winfrey, ranked 21 in the Forbes list of the world's most powerful women, is scheduled to appear at campaign hustings for the Illinois senator in the first contests in the 2008 race for the White House.

The billionaire media mogul is due in Iowa on December 8 - less than a month before the caucus vote on January 3 - with stops in Des Moines and Cedar Rapids. The following day she is due to head for Columbia, South Carolina, and Manchester, New Hampshire.

Hitting the campaign stump for Obama will mark a new level of involvement for Winfrey. In September, she led a fund raiser in California that amassed about $3m (£1.45m) for his campaign.

Winfrey called Obama "my favorite guy" and "my choice" on CNN's Larry King Live last year, before he announced his decision to run for the White House.

Obama will hope that Winfrey's enormous popularity translates into actual votes. Her eponymous show, stressing spirituality and reinvention, has topped the daytime talk show ratings for 21 years, pulling in 48 million viewers a week in the US.

A vocal advocate for the education and protection of women and children around the world, she recently opened the Oprah Winfrey leadership academy for girls in South Africa, which was in the news earlier this month following allegations of sexual abuse charges against a female member of staff.

Recent polls show Obama pulling level with Hillary Clinton, the Democratic front-runner, in the Iowa caucus.

According to a Washington Post/ABC poll, Obama had 30% support, followed by Clinton at 26% and John Edwards, John Kerry's running mate in 2004, at 22%. The gaps between leaders were within the poll's 4.5% margin of error, suggesting - as polls have shown for a while - a tight three-way race in the state.

Clinton, a two-term senator from New York, has downplayed the survey, saying that she doesn't pay attention to any of the polls. Yet when asked recently how she would beat a Republican nominee, Clinton cited polls showing that she had greater national appeal than her Democratic rivals.