Sen. Marco Rubio, R-Fla., the son of Cuban immigrants, has urged his fellow conservatives to soften their rhetoric on illegal immigration. Above, he makes a campaign stop with Republican presidential candidate Mitt Romney on Monday in Aston, Pa. Jessica Kourkounis/Getty Images hide caption

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Hikers arrive at the post office in Caratunk, Maine, in 2011. Some of the rural post offices the U.S. Postal Service may close are relied on by Appalachian Trail hikers for supply drops on their trip from Georgia to Maine. Robert F. Bukaty/AP hide caption

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Back in 1868, this was how the Office of the Secretary of the Senate prepared the summons for President Andrew Johnson to appear before the court of impeachment. Today, the secretary of the Senate continues to rely on paper to record campaign contributions. Library of Congress hide caption

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A tax service company in Brooklyn, N.Y, on Tuesday, the filing deadline for federal taxes. Mary Altaffer/AP hide caption

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Rep. Darrell Issa, R-Calif., chairman of the House oversight committee, made news recently for going after the Justice Department's botched gun operation, known as Fast and Furious. Here, Issa listens during Attorney General Eric Holder's testimony in February. Kevin LaMarque/Reuters/Landov hide caption

itoggle caption Kevin LaMarque/Reuters/Landov

President Obama speaks at the San Pedro Claver church in Cartagena, Colombia, on Sunday. An expert on the Secret Service tells NPR that Obama's security was never breached in the incident that led to 11 U.S. Secret Service agents being sent home amid allegations that they hired prostitutes in Cartagena. Carolyn Kaster/AP hide caption

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House Budget Committee Chairman Rep. Paul Ryan, R-Wis., with his 2012 budget plan. Ryan cites his Catholic faith in justifying his proposed cuts to social safety-net programs. Jacquelyn Martin/AP hide caption

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Pennsylvania State Rep. Bill DeWeese (right) has been convicted of corruption but is running for re-election nonetheless. Bradley C. Bower/AP hide caption

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