Leftist candidate won’t concede Mexico presidency

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Supporters of Enrique Pena Nieto, presidential candidate for the Revolutionary Institutional Party (PRI) gather at party headquarters as exit polls begin to come in for general elections in Mexico City, Mexico, Sunday, July 1, 2012. Pena Nieto is leading Mexico's elections with about 40 percent of the vote, exit polls showed Sunday, signaling a return of his long-ruling party to power after a 12-year hiatus. (AP Photo/Alexandre Meneghini)Leftist candidate Andres Manuel Lopez Obrador says he won't concede the presidency despite an official preliminary count that shows him losing to former ruling party candidate Enrique Pena Nieto.