Leftist Andres Manuel Lopez Obrador has claimed victory in Mexico's presidential election, calling for reconciliation after what he called a "historic day."
He spoke late Sunday shortly after electoral authorities announced that a quick count forecast he had gotten more than half the votes, a remarkable mandate not seen in the country for many years.
President Enrique Pena Nieto said in a televised message to the nation that he had congratulated Obrador.
Obrador supporters were wildly celebrating his win even before authorities released official results.
President Trump weighed in, tweeting that he looks forward to working with Obrador:
Congratulations to Andres Manuel Lopez Obrador on becoming the next President of Mexico. I look very much forward to working with him. There is much to be done that will benefit both the United States and Mexico!— Donald J. Trump (@realDonaldTrump) July 2, 2018
Thousands of people poured into Mexico City's sprawling main square, known as the Zocalo, where the 64-year-old former mayor had called on his backers to rally Sunday night.
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Retired Susana Zuniga beamed as she said the country was experiencing a moment similar to the Mexican Revolution a century ago.
In her words: "The people are fed up, that is what brought us to this."
Motorists were cruising up and down the central Paseo de la Reforma, honking horns to the tune of "Viva Mexico!" and waving Mexican flags from car windows and moon roofs.
Earlier Sunday, Jose Antonio Meade of Mexico's ruling party conceded defeat to Obrador. In a tweet hours later, he wrote in Spanish: "Thanks to the millions of Mexicans who voted for me, who voted for a Mexico where the rule of law reigns and where everyone has the necessary tools to fulfill their goals and dreams."
In his remarks, Obrador vowed that profound change is coming, but said individual and property rights would be guaranteed. He promised respect for the autonomy of the Bank of Mexico and said his government will maintain financial and fiscal discipline.
He also said contracts obtained under energy reforms will be scrutinized for any corruption or illegality, but there would be no confiscation or expropriation of property.
The Associated Press contributed to this report.