The chat queen pipped Fox News Channel commentator Glenn Beck in the survey headed by Harris Poll.
Jay Leno, who was recently named to return as host of The Tonight Show in place of Conan O'Brien, bagged the third spot, reports the New York Post.
Ellen DeGeneres finished fourth, tied with actor Hugh Laurie of House.
Image: Oprah Winfrey displays her award at the 54th annual Emmy Awards in Los Angeles
Photograph: Mike Blake/Reuters
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