Andres Manuel Lopez Obrador, presidential candidate for the Democratic Revolution Party (PRD), attends a news conference in Mexico City, Wednesday, July 18, 2012. Lopez Obrador claims that the ... more 
Andres Manuel Lopez Obrador, presidential candidate for the Democratic Revolution Party (PRD), attends a news conference in Mexico City, Wednesday, July 18, 2012. Lopez Obrador claims that the campaign of Enrique Pena Nieto, presidential candidate for the Revolutionary Institutional Party (PRI) engaged in overspending and vote buying. (AP Photo/Eduardo Verdugo) less 
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Associated Press | Photo By Eduardo Verdugo
Fri, Jul 20, 2012 1:33 PM EDT