Brazil's presidential race is headed for a runoff after Sen. Flávio Bolsonaro, the son of jailed former president Jair Bolsonaro and a close ally of Donald Trump, outpolled incumbent Luiz Inácio Lula da Silva in Sunday's first-round vote. With roughly 98% of ballots counted, Flávio Bolsonaro held 47.45% of the valid vote to Lula's 44.66%, according to Brazil's electoral authority — a result that NBC News and other outlets called a stunning reversal of the final pre-election surveys.

Most major polls published in the days before the vote had shown Lula, 80, finishing first, some by margins of 3 points or more. Instead it was Flávio Bolsonaro, 45, who topped the field, setting up an Oct. 25 runoff that will decide whether Lula wins a fourth, nonconsecutive term or hands power to a political dynasty that Trump has publicly championed.

A "Protest Vote" Surge

Analysts told Reuters they believe much of Flávio Bolsonaro's first-round strength came from "protest votes" — ballots cast against Lula rather than enthusiastically for the senator — that pollsters had expected voters to hold back for the second round. NPR reported the first round played out against a backdrop of corruption scandals, deep polarization and voter fatigue after nearly four years of Lula's third term.

NEITHER CANDIDATE CLEARED THE 50% THRESHOLD NEEDED TO WIN OUTRIGHT

The race has taken on outsize international weight. CNN noted the campaign has been dominated as much by Trump's shadow as by domestic crime and corruption fights, with Flávio Bolsonaro's rise tracking his father's continued detention and his own courtship of Washington. His father, former president Jair Bolsonaro, remains under house arrest in Brazil on charges tied to an alleged coup plot after his 2022 election loss.

Lula, who has governed since 2023 after previously serving two terms in the 2000s, now faces the tightest reelection fight of his career. Newsweek reported surveys taken before Sunday's vote had shown the two men roughly even in a hypothetical runoff, suggesting the Oct. 25 contest is a true toss-up.

What's Next

With other candidates eliminated, the next three weeks will be a sprint for the political center — union households, young voters and the moderate electorate that neither hardline camp has locked down. Both campaigns are expected to court undecided voters with promises on crime, the economy and Brazil's relationship with Washington, where Trump has made no secret of his preference. The runoff on Oct. 25 will determine not just Brazil's next president, but whether the Bolsonaro name returns to Latin America's largest seat of power.