 Perhaps Obama's biggest celebrity endorsement is talk show host Oprah Winfrey, who has occasionally joined Obama on the campaign trail and hosted a fundraiser at her Santa Barbara, CA estate.After his win in South Carolina Obama received the endorsement of Caroline Kennedy, the daughter of President John F. Kennedy, and Ted Kennedy, his brother.For the first time in its ten-year history, MoveOn.org endorsed a presidential candidate when Obama received 70 percent of an online ballot the organization held of its members.