New York City Mayor Bill de Blasio signs an executive order raising the city's living wage law Tuesday. The move will require some employers to pay their employees between $11.50 and $13.13 an hour, depending on whether the employee receives benefits. Andrew Burton/Getty Images hide caption

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Darlene Handy of Baltimore holds up a banner at a rally supporting a pay measure in Maryland. More than 20 states have raised minimum pay rates above the federal level. Jose Luis Magana/AP hide caption

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A Denny's waitress delivers breakfast to customers in Emeryville, Calif. The tipped minimum wage has been stuck at $2.13 since 1991. Justin Sullivan/Getty Images hide caption

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President Obama, working at his desk Monday night on the eve of his 2014 State of the Union address. Jacquelyn Martin/AP hide caption

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Protesters rally outside of a Wendy's in Brooklyn, New York, on Dec. 5 in support of raising fast food wages from $7.25 to $15 per hour. Andrew Burton/Getty Images hide caption

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Fast-food workers march toward the Smithsonian's National Air and Space Museum in Washington, D.C., on Thursday. Similar rallies occurred in about 100 cities across the U.S. Morgan Walker/NPR hide caption

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Voters in SeaTac, Wash., have narrowly approved a measure raising the minimum wage at its international airport, officials say. But the initiative faces several challenges, including a recount. Elaine Thompson/AP hide caption

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