Andres Manuel Lopez Obrador, presidential candidate for the Democratic Revolution Party (PRD), speaks during a news conference in Mexico City, Thursday, July 05, 2012. Lopez Obrador alleges that ... more 
Andres Manuel Lopez Obrador, presidential candidate for the Democratic Revolution Party (PRD), speaks during a news conference in Mexico City, Thursday, July 05, 2012. Lopez Obrador alleges that Enrique Pena Nieto’s Institutional Revolutionary Party, or PRI, engaged in vote-buying that illegally tilted millions of votes toward the party that ruled Mexico with nearly virtual control for seven decades, until it lost the presidency in 2000. By late Thursday, PRI's candidate Pena Nieto was leading the vote count with 38.3 percent, compared to 31.5 percent for Lopez Obrador and 25.5 percent for Josefina Vazquez Mota, presidential candidate of the ruling National Action Party (PAN). (AP Photo/Alexandre Meneghini) less 
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Associated Press | Photo By Alexandre Meneghini
Thu, Jul 5, 2012 11:06 PM EDT