By: The Washington Post Published: Saturday, November 24, 2012, 7:16 p.m. Updated: Monday, November 26, 2012 OXFORD, Miss. — Election Day in the South told a surprising story: The nation’s first black president finished more strongly in the region than any Democratic nominee in three decades, underscoring a fresh challenge for Republicans who rely on Southern whites as their base of national support. President Obama won Virginia and Florida and narrowly missed victory in North Carolina. But he also polled as well in Georgia as any Democrat since Jimmy Carter, grabbed 44 percent of the vote in deep-red South Carolina and just under that in Mississippi — despite doing no substantive campaigning in any of those states.