This combo picture of three file photos shows presidential candidates, from left, Enrique Pena Nieto of the Institutional Revolutionary Party, PRI, Josefina Vazquez Mota of the National Action Party, ... more 
This combo picture of three file photos shows presidential candidates, from left, Enrique Pena Nieto of the Institutional Revolutionary Party, PRI, Josefina Vazquez Mota of the National Action Party, PAN, and Andres Manuel Lopez Obrador of the Democratic Revolutionary Party, PRD, during different events in Mexico City. Mexico will hold presidential elections on July 1, 2012. (AP Photo, Files) less 
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Associated Press
Thu, Mar 1, 2012 9:47 PM EST