Presidential candidate Andres Manuel Lopez Obrador, of the Democratic Revolution Party (PRD), speaks during an event hosted by the non-governmental organization Mexico SOS, that advocates security and... more 
Presidential candidate Andres Manuel Lopez Obrador, of the Democratic Revolution Party (PRD), speaks during an event hosted by the non-governmental organization Mexico SOS, that advocates security and justice, in Mexico City, Monday April 2, 2012. The four candidates for Mexico's presidency officially launched their campaigns for the July 1 election on Friday, all of them promising change. (AP Photo/Alexandre Meneghini) less 
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Associated Press | Photo By Alexandre Meneghini
Wed, Apr 4, 2012 9:05 AM EDT