American Federation of Labor and Congress of Industrial Organizations President Richard Trumka addresses members during the quadrennial AFL-CIO convention at Los Angeles Convention Center in Sept. 2013. Nick Ut/AP hide caption

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New Jersey Gov. Chris Christie speaks to the Economic Club of Chicago on Tuesday. Christie was in town to raise money for the Republican Governors Association. PAUL BEATY/AP hide caption

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Presidents past and present were on hand for the opening ceremony for the George W. Bush Presidential Center in Dallas in April 2013. Kevork Djansezian/AP hide caption

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Republican National Committee chairman Reince Priebus is seen at the Jan. 24 RNC winter meeting in Washington. Priebus celebrates the achievements of black Republicans in a series of new radio ads designed to honor Black History Month. Susan Walsh/AP hide caption

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Mike Huckabee, left, sits with RNC Chairman Reince Priebus before Huckabee spoke at the Republican National Committee winter meeting in Washington on Thursday, Susan Walsh/AP hide caption

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Republican Ed Gillespie announced Thursday that he's challenging Democratic Virginia Sen. Mark Warner in November's election. Gillespie, a senior adviser to Republican Mitt Romney in the 2012 presidential race, is shown here at Romney's election night rally in Boston on Nov. 6, 2012. Mike Segar/Reuters/Landov hide caption

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Trish Gallagher holds a sign for passing motorists to read during a demonstration in support of a higher minimum wage near a Burger King in Boston on Dec. 5. Massachusetts is one of several states considering a minimum wage ballot measure. BRIAN SNYDER/Reuters/Landov hide caption

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Republican Sen. Marco Rubio of Florida delivers a speech on reforming antipoverty programs on the 50th Anniversary of President Johnson's declaration of the "War on Poverty." Kevin Dietsch/UPI/Landov hide caption

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Sen. Rand Paul (R-Ky.) greets supporters during a tea party rally in front of the U.S. Capitol in June. Paul was a rising star in the tea party movement this year, filibustering a CIA nomination in March. Mark Wilson/Getty Images hide caption

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An auto worker tightens bolts on a Focus at a Ford plant in Michigan in October. Labor unions predicted in 1993 that NAFTA would send many U.S. manufacturing jobs to Mexico, and they continue to argue that the pact prompted a race to the bottom for workers. Mira Oberman/AFP/Getty Images hide caption

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Rep. Darrell Issa, a California Republican and chairman of the House Oversight and Government Reform Committee, planned to hold at least four field hearings on the Affordable Care Act, which he blames for increased health insurance prices. Mark Wilson/Getty Images hide caption

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Supporters may be "Ready for Hillary," but NPR political reporter Don Gonyea isn't. Kevork Djansezian/Getty Images hide caption

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