CEDAR RAPIDS, Iowa (CNN) -- Saying she felt compelled to support "the man I believe has a new vision for America," Oprah Winfrey spoke passionately about Democratic presidential hopeful Barack Obama at two rallies in Iowa Saturday. Oprah Winfrey joins Democratic presidential candidate Barack Obama at a rally in Des Moines, Iowa, Saturday. "I've never taken this kind of risk before nor felt compelled to stand up and speak out before because there wasn't anyone to to stand up and speak up for," Winfrey told thousands of people in Cedar Rapids Saturday evening. "We need a president who can bring us all together," she said. "I know [Barack Obama] is the one."
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NEW: Winfrey: "We need a president who can bring us all together"
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"Oprah-bama" hits Iowa on Saturday; South Carolina, New Hampshire on Sunday
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Winfrey a boost as Obama tries to steal women voters from Hillary Clinton
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Clinton campaign plays down effect Winfrey will have on swaying voters
@placeholder's campaign appearance comes less than one month before the Iowa caucuses.