According to Politico, Winfrey is expected to promote Obama's health care reform and his call for tighter gun control norms.
Her high-profile endorsement of Barack Obama over Hillary Clinton in the 2008 presidential elections has been the only contribution to federal office in last two decades.
Craig Garthwaite, a Northwestern University professor who studied Oprah's effect on the election, said that they had estimated that her endorsement of Obama had amounted to approximately a million additional votes in the 2008 Democratic primary elections.
Winfrey also hosted a fundraiser event for Newark Mayor Cory Booker in the New Jersey Senate contest.
Observers have claimed that although her career-defining daily talk show is off the air, Oprah's political activity still packs a punch.
Winfrey's authenticity and familiarity makes her word matter more than that of other politically involved stars.
--ANI (Posted on 13-08-2013)