“You can feel it, you can feel it, President Milei!” Crowds sang until the late hours of the night after a self-proclaimed “anarcho-capitalist,” Javier Milei, won on Sunday night the primary elections in Argentina, emerging as the main candidate for the general election in October and sending shockwaves through the country.

A devotee of the Austrian school of economics, Mr. Milei claims to be the libertarian savior of the country. He wants to shutter Argentina’s central bank, adopt the American greenback as the country’s currency, overturn abortion laws, and slash government spending. He has long criticized the “political caste,” saying the state is the enemy and politicians are “parasites” motivated by their own greed. 

“Today we took the first step toward the reconstruction of Argentina,” Mr. Milei declared Sunday to his audience at Buenos Aires while dedicating his triumph to his four dogs. “A different Argentina is impossible with the same people as always.”

Mr. Milei’s party, Liberty Moves Forward, won 30.2 percent of the vote and triumphed in 16 out of the 23 provinces. The two candidates for the right-wing United for Change, Patricia Bullrich and Horacio Rodriguez Larreta, won a total of 28.2 percent. The candidates for governing left-wing Union for the Homeland, Sergio Massa and Juan Grabois, summed up at only 27.1 percent. 

Nobody anticipated the results. Polls throughout the country had been placing Mr. Milei in third place this year. “Javier Milei won the primaries and caused an earthquake in Argentine politics,” the headline for an article published by the newspaper La Nacion says. “Surprising election of Javier Milei, who won with more than 30 percent of the votes,” a headline of an Infobae article says. 

From the bunker of Union for Change, Ms. Bullrich, who will face Mr. Milei in the general election on October 22, congratulated her libertarian counterpart for the “massive” election campaign he held and for contributing to the general debate in Argentina. She also assured her followers that, just like them, Mr. Milei doesn’t want the state to be a place for the left-wing political party. 

President Macri, also a part of Ms. Bullrich’s party, said that Mr. Milei’s triumph represents a general dissatisfaction with politics. A “huge majority” wants to see a “profound change that has not existed in decades in Argentina,” he added.

Mr. Milei began to appear in the political sphere in 2018 with his disruptive ideas breaking the status quo imposed by the two dominant parties in the country. A video depicting the candidate smacking a pinata shaped like the Central Bank, which was posted on national TV on Mr. Milei’s 48th birthday in 2018, went viral. 

In 2020, Mr. Milei announced his candidacy for the 2023 elections, and the following year, his party won two seats in Congress: one occupied by him and the other by his current vice president in the formula, Victoria Villarruel. 

If elected, Mr. Milei said he would take a “chainsaw” to public spending. In a video introduction to his initiative, he calls politicians “criminals” and “thieves.” He says his plan would deprive them of “the opportunity to steal and will have to work like honest people.”  

Mr. Milei also favors open-carry gun laws. Under Argentina’s current law, civilians must in order to own a gun apply for a permit, which is difficult to obtain.