Rep. Ron Paul waits to speak at a news conference in April in Des Moines, Iowa. Charlie Neibergall/AP hide caption

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Then-House Speaker Newt Gingrich holds up a copy of the Republican Party's "Contract with America" during a rally to celebrate the first 50 days of the Republican majority in Congress in 1995. Joshua Roberts/AFP/Getty Images hide caption

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Rep. Michele Bachmann (R-MN), holding a stack of petitions, addresses a "Code Red" rally on Capitol Hill in March 2010, sponsored by The American Grassroots Coalition and the Tea Party Express. The rally was in opposition to the health care overhaul bill. Chip Somodevilla/Getty Images hide caption

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Huckabee signs a copy of his new book, A Simple Government: Twelve Things We Really Need from Washington (and a Trillion that We Don't!), at the National Press Club, February 2011 in Washington. Chip Somodevilla/Getty Images hide caption

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Herman Cain speaks at a Tea Party Tax Day rally this April outside the Statehouse in Concord, N.H. The former Atlanta talk show host and businessman is testing a possible presidential run. Darren McCollester/Getty Images hide caption

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Delaware County District Attorney Patrick Meehan (from left) and Gail Willard (mother of slain athlete Aimee Willard) accompany Sen. Rick Santorum as he introduces "Aimee's Law" along with Republican Arizona Rep. Matt Salmon at the county courthouse in Media, Pa., in 1999. The bill encourages states to keep murderers and sexual predators behind bars. William Thomas Cain/AP hide caption

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A newspaper clipping from 1966 announces Mitch Daniels (second from left) as the recipient of the Graham Award, presented to the most outstanding citizen at Hoosier Boys State at Indiana University. Courtesy of The Office of Governor Mitch Daniels hide caption

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Sarah Palin (center) stands with the Wasilla, Alaska, City Council for a portrait in 1998. In 1992, then-Mayor John Stein recruited Palin as a moderate counterweight to the growing anti-government, anti-tax movement. By 1996, Palin challenged Stein in the race for mayor — and won. Heath Family/AP hide caption

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Jon Huntsman, the outgoing U.S. ambassador to China, briefs reporters in November 2009. If Huntsman joins the field of presidential candidates, he may have a difficult time explaining to Republican primary voters why he worked for a Democratic president. Charles Dharapak/AP hide caption

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George Romney with his wife, Lenore, and teenage son Mitt, after announcing he would seek the Republican nomination for governor of Michigan at a press conference in 1962. AP hide caption

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Then-gubernatorial candidate Tim Pawlenty and running mate Carol Molnau celebrate their victory at Republican election headquarters on Nov. 6, 2002, in Bloomington, Minn. The former governor says he was inspired by Ronald Reagan — someone who wasn't considered such a hero 30 years ago in Pawlenty's blue-collar neighborhood. Andy King/AP hide caption

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