President Lyndon Johnson talks with civil rights leaders in his White House office on Jan. 18, 1964. The black leaders, from left, are, Roy Wilkins, James Farmer, Dr. Martin Luther King Jr., and Whitney Young. AP hide caption

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President Obama stands on stage with Vice President Biden and their families after accepting the party nomination during the final day of the 2012 Democratic National Convention in Charlotte, N.C. Alex Wong/Getty Images hide caption

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Sen. Dianne Feinstein, D-Calif., speaks with reporters after alleging that the CIA broke federal law by secretly removing sensitive documents from computers used by the Senate Select Committee on Intelligence, the committee tasked with congressional oversight of the CIA. Win McNamee/Getty Images hide caption

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Campaign workers and other political operatives are trying to find ways to use Google Glass on the campaign trail. Frederic J. Brown /AFP/Getty Images hide caption

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At CPAC this year, even Sen. Rand Paul's cardboard cutout was drawing attention. The Kentucky lawmaker was leading in the straw poll among attendees Friday. Jim Lo Scalzo/EPA/Landov hide caption

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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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