BOGOTA — Colombia's presidential election will go to a runoff on June 21 between pro-Trump lawyer Abelardo de la Espriella and leftist Senator Ivan Cepeda, after neither cleared the 50 percent threshold in Sunday's first round and outgoing President Gustavo Petro refused to accept the preliminary count.

With essentially all ballots tallied, de la Espriella led with about 43 percent and Cepeda trailed at roughly 41 percent, Colombia's electoral authorities said. Paloma Valencia, the Centro Democratico candidate and protege of former President Alvaro Uribe, finished a distant third with less than 7 percent and endorsed de la Espriella at a news conference Sunday.

What is at stake

The runoff sets up a stark choice over how Colombia confronts armed groups a decade after the 2016 peace pact with the Revolutionary Armed Forces of Colombia, or FARC. Cepeda, who helped negotiate that accord and is an ally of Petro, has pledged to continue the "total peace" push to negotiate with remaining rebel and criminal organizations. De la Espriella, who calls himself "The Tiger," has promised to emulate El Salvador President Nayib Bukele's mass-incarceration model, including a proposal to build 10 maximum-security megaprisons.

The contest is also a test of U.S. influence in the region. De la Espriella has aligned himself with President Trump, and Sen. Bernie Moreno, R-Ohio, plans to return to Colombia as an international observer for the second round. Rep. Maria Elvira Salazar, R-Fla., endorsed de la Espriella before the vote.

The count dispute

Petro said Sunday night he would not accept the preliminary tally released by the National Civil Registry, claiming that software used by private companies to count votes was flawed and that 800,000 identification numbers in the system did not match the official census. Cepeda echoed the complaint in a speech in Bogota. "Today, we secured 10 million votes that were miscounted in Colombia," Cepeda said. "There is a discrepancy that we wish to verify."

The registry's chief, Hernan Penagos, said in March that the preliminary count of this year's congressional elections matched the final results to 99.8 percent precision. Juanita Goebertus, the Americas director of Human Rights Watch, called Colombia's electoral system "independent and trustworthy" in a post on X and said it was "regrettable that the president is sowing unjustified doubts."

De la Espriella celebrated on the same platform. "We will defeat tyranny and absolutism," he wrote, adding that he had reached the runoff thanks to "the more than 10 million Colombians who answered to the roar."

The counterpoint

Petro and Cepeda say the count is unreliable and that the registry's software admitted hundreds of thousands of ineligible voters; election observers and the registry itself say the preliminary tally has matched final results to within a fraction of a percent in recent Colombian votes, and Human Rights Watch has urged the international community to back the official outcome. Both positions will follow the candidates into the second round.

What comes next

Voters return to the polls on June 21. Valencia's roughly 7 percent now becomes the most contested bloc in Colombian politics, and de la Espriella is positioned to absorb most of it. Moreno said on X that he would be back to observe. "Democracy won today, but the work isn't done yet," he wrote.