Sen. Flávio Bolsonaro, an ally of U.S. President Donald Trump, and Brazil's incumbent President Luiz Inácio Lula da Silva will face off in a runoff Oct. 25 for the top job of Latin America's powerhouse economy after neither won a majority in Sunday's vote.

The country's electoral court in Brasilia said neither the 80-year-old incumbent, seeking his fourth non-consecutive term, nor the 45-year-old son of former President Jair Bolsonaro would garner the majority vote needed for an outright win.

The court had Bolsonaro with just over 56 million votes to Lula's 53.7 million, with 99.8 percent of the vote reported. The next presidential term is set to begin Jan. 5.

The winner will be in charge of Latin America's biggest economy and a population of 214 million. A win for Bolsonaro would increase U.S. influence in Latin America. If Lula wins, Brazil will keep its distance from Washington and continue to deepen its relationship with China.

Flávio Bolsonaro addressed the press and a small group of supporters, including some wearing green and yellow Brazil jerseys and one woman wrapped in the Israeli flag, outside his Brasilia house.

"Brazil wants change, that's the reading of what happened today," Bolsonaro said. "It's the end of the Workers' Party era," he added, in a reference to Lula's party. Lula, seeking to be encouraging ahead of an uphill battle to beat Bolsonaro in the runoff, said the result was "unexpected" as he had thought he could win in the first round.

"Tomorrow we start a new campaign," Lula said. "I am very good in the knockout stage. We will see who has the best plan."

Both Lula and Bolsonaro will have three weeks to reach moderate voters who did not support them in the first round. Augusto Cury, a writer who finished in third place with 3.4 million votes, said he would not endorse either in the runoff. Ronaldo Caiado and Renan Santos, two candidates who garnered about 5.3 million votes combined Sunday, have previously said the same.

In the campaign ahead, Lula is expected to try to capitalize on the popularity of his social policies and his rival's many legal woes.

While the once widely popular Lula saw his approval ratings plummet during his third term, standing up to the U.S. gave him a boost. And he still enjoys a strong base of supporters who credit his social policies for improving millions of Brazilians' lives.

Bolsonaro will likely lean into his messaging on affordability and link the president to corruption scandals.

He has promised to crack down on Brazilian criminal groups and insisted that Brazil needs to strike better deals with the Trump administration, including in the rare minerals economy, second only to China. Bolsonaro also has campaigned on releasing his father and bringing him back to politics.

Both candidates face image problems: Roughly half of Brazil's population disapproves of the Bolsonaro family, and roughly half disapprove of Lula's Workers' Party, according to multiple polls.

Four years ago, Lula beat then incumbent Jair Bolsonaro by about 2.1 million votes.

While it was a successful night for Bolsonaro, nothing is won yet, said Mayra Goulart, a political scientist from the Federal University of Rio de Janeiro. Lula should "look at the votes for Augusto Cury and Ronaldo Caiado and try to reduce abstention," she said.

Reacting to the result, Alvaro Senra, 65, a history professor and Lula supporter in Rio de Janeiro said he felt "calm but very sad." He watched the count with friends at a bar.

"I think this is the result of conservatives working under the radar, including by neo-Pentecostal churches. But I think Lula can still win," he said.

Earlier in the day, Maria Ribeiro, a 50-year-old cellphone vendor from Brasilia, said she voted for Bolsonaro's eldest son because she wants freedom to express her evangelical religion. She hopes he follows in his father's footsteps.