Former Maryland Gov. Martin O'Malley, Sen. Bernie Sanders, I-Vt. and Hillary Clinton at the NBC News-YouTube Democratic presidential debate at the Gaillard Center on Sunday in Charleston, S.C.
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Iranian President Hassan Rouhani presents the draft budget for the next Iranian fiscal year to the chairman of the Iranian Parliament Ali Larijani at the Iranian parliament in Tehran on Jan. 17, 2016.
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President Obama said he regrets that the rancor between the parties has grown during his watch. "I guarantee I'll keep trying to be better so long as I hold this office," he said.