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Institutional Revolutionary Party, or PRI, candidate Enrique Peña Nieto won Mexico's presidency with 38.02 percent of the vote, putting him more than six percentage points ahead of his nearest rival, preliminary results released Monday by the Federal Electoral Institute, or IFE, show.
Some 95.05 percent of the ballots had been counted as of 1:15 p.m., the IFE said, adding that the tally was continuing.
Figures from the Preliminary Election Results Program, or PREP, will continue to be released until 8:00 p.m., the IFE said.
Peña Nieto, who is also the candidate of the Mexican Green Party, or PVEM, may have received nearly 18.1 million votes, putting him firmly in first place.
Andres Manuel Lopez Obrador, candidate of the leftist Progressive Movement coalition, got 31.73 percent, or 15.1 million votes, while governing National Action Party, or PAN, standard-bearer Josefina Vazquez Mota, the only woman in the race, came in third, getting 25.45 percent, or 12.1 million votes.
Gabriel Quadri, of the New Alliance Party, or PANAL, got 2.3 percent, or 1.1 million votes.
The rest of the ballots - less than 2.5 percent - were void, cast for unregistered candidates or blank.
Voter turnout for the election was 63.17 percent, well above the 60 percent projected.
Peña Nieto vowed to work for reconciliation and national unity while crafting a "modern and responsible" presidency.
He said he would continue to fight organized crime, but with a new strategy that focuses on reducing violence and safeguarding the lives of Mexicans.
"Let it be clear. There will be no pact or truce with organized crime," the 45-year-old Peña Nieto said, referring to the wave of drug-related violence that has claimed the lives of more than 50,000 people since late 2006.
Peña Nieto thanked the millions of Mexicans who placed their trust in him and promised to take the presidency in a new direction.
Mexico will have "a modern presidency, responsible, open to criticism, and willing to listen and take everyone into account," Peña Nieto said.
Sunday's election gives the PRI, which governed Mexico from 1929 to 2000, a second chance, Peña Nieto said.
The PRI lost the 2000 and 2006 presidential elections to the PAN.
"The country wants work, cooperation and, above all and most importantly, results," Peña Nieto said.
Lopez Obrador has not conceded yet, saying that the figures released by the IFE did not match the numbers gathered by his campaign.
"The last word has not been spoken," Lopez Obrador said. "It is important to have a recount of all the figures ... We are going to wait until we have all the information."
Lopez Obrador, a former Mexico City mayor, lost the 2006 presidential election to Calderon by 0.56 percent and has never recognized the results.
U.S. President Barack Obama called Peña Nieto on Monday to congratulate him on his victory.
"Today, the President called Enrique Peña Nieto, President-elect of Mexico, to congratulate him on his victory based on the initial results issued by Mexico's electoral authorities. The two leaders reaffirmed the close bilateral partnership the United States and Mexico enjoy based on mutual respect, shared responsibility, and the deep connections between our people," the White House said in a statement.
The PRI, based on preliminary results, won the governorships of Chiapas, with Manuel Velasco; Jalisco, with Aristoteles Sandoval; and Yucatan, with Rolando Zapata Bello.
The PRD retains control of Mexico City, whose mayoralty was won by Miguel Angel Mancera and Morelos state, where Graco Ramirez won.
The PAN will continue to govern Guanajuato under Miguel Angel Marquez.
The gubernatorial race in Tabasco is extremely tight, with the PRD candidate getting 37.1 percent of the vote and the PRI candidate garnering 36.2 percent, with more than 90 percent of the ballots counted.
The preliminary results are not legally valid because they must be certified.
Peña Nieto will succeed President Felipe Calderon, of the PAN, on Dec. 1. EFE