Former Florida Gov. Jeb Bush's campaign dismissed the no-new taxes pledge as something "circulated by lobbying groups" and he says he "will not sign." David Goldman/AP hide caption

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Gov. Scott Walker arrives at the First in the Nation Republican Leadership Summit in New Hampshire. Walker has long been a polarizing figure due to his epic battles with public employee unions, but a new poll this week shows a new and sizable drop in his approval rating. Darren McCollester/Getty Images hide caption

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Democratic presidential candidate Hillary Clinton is facing questions about money, access and influence while she was secretary of state. Jacquelyn Martin/AP hide caption

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Senate Minority Leader Harry Reid, D-Nev., (left) and Majority Leader Mitch McConnell, R-Ky., at a ceremony last month at the U.S. Capitol. Chip Somodevilla/Getty Images hide caption

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Attorney general nominee Loretta Lynch testifies on Capitol Hill in January. Lynch was confirmed by the Senate on Thursday after months of delay and partisan bickering. Jacquelyn Martin/AP hide caption

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"Part of the reason we're here is because climate change is threatening this treasure and the communities that depend on it," Obama said Wednesday of his visit to Everglades National Park in Florida. "If we don't act, there may not be an Everglades as we know it." Mandel Ngan/AFP/Getty Images hide caption

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