The ambulance transporting Brazilian presidential candidate Jair Bolsonaro, who was stabbed during a campaign event, arrives at the Albert Einstein Hospital, where the candidate was transferred, in Sao Paulo, Brazil, Friday, Sept. 7, 2018. Surgeon Luis Borsato said Bolsonaro was in serious but stable condition and would remain in intensive care for at least seven days. (AP Photo/Marcelo Chello)

SAO PAULO - Brazil's presidential race was thrown into chaos on Friday with the far-right front-runner in serious but stable condition after being stabbed at a rally one month before the vote.

Congressman Jair Bolsonaro was knifed in the stomach while being carried atop supporters' shoulders in a street rally on Thursday and was being treated at a Sao Paulo hospital.

The attack further clouds Brazil's most unpredictable election in three decades. Corruption investigations have jailed scores of powerful businessmen and politicians in recent years, and alienated infuriated voters.

Bolsonaro, 63, has for years angered many Brazilians with extreme statements, but is also seen by his many supporters as a politically incorrect gust of fresh air in a rotten system.

He has repeatedly said the country's notoriously violent police should increase their killing of suspected drug gang members and armed criminals. That plays well with wealthier voters, but is terrifying for the one-third of Brazilians who tell pollsters they are as afraid of police as criminals.

Surveys consistently give Bolsonaro around 22% in simulated first-round votes. However, those polls find he would badly lose to most rivals in the likely event of a runoff, which takes place if no candidate wins a majority in the first ballot.

ELECTION BOOST?

Some Bolsonaro backers and analysts, especially in financial markets, forecast the attack could give Bolsonaro a huge boost. They argue is will draw in some of the 28% of voters who say they are undecided or will not vote for anyone.

"I just want to send a message to the thugs who tried to ruin the life of a family man, a guy who is the hope for millions of Brazilians: You just elected him president. He will win in the first round," Flavio Bolsonaro, the candidate's son, said on Friday, echoing sentiment many spread across social media.

Carlos Melo, a political scientist with Insper, a Sao Paulo business school, said Bolsonaro may gain some votes. But he doubted there would be a big shift his way, especially given that 44% of those surveyed in the latest Ibope poll say they would never cast a ballot for Bolsonaro, the stiffest rejection for any candidate.

"I see no reason why voters who have previously said they reject him would now automatically support him," Melo said.

The political scientist thinks that once the commotion of the attack passes, voters may soberly think about the roots of the political polarization and aggressive rhetoric that has engulfed Brazil.

"Jair Bolsonaro is a symbol of that process," Melo said. "Voters may be awakened to the thought that politicians who propose loosening gun laws, for example, end up giving unbridled power to crazy people, like the man who carried out the attack yesterday."

LITTLE TIME

Bolsonaro was stabbed while being carried on someone's shoulders in a crowd of cheering supporters in the city of Juiz de Fora.

TV pictures showed him screaming in pain, then falling backward into the arms of those around him.

Police video taken at a precinct showed suspect Adelio Bispo de Oliveira telling police he had been ordered by God to carry out the attack.

Speaking earlier in an online video from hospital in Juiz de Fora, Bolsonaro said the pain of the attack at first was like being hit by a soccer ball.

"It was intolerable and it seemed like maybe something worse was happening," he said, talking in a weak, raspy voice with a tube in his nose and monitors beeping nearby. "I was preparing for this sort of thing. You run risks."

Bolsonaro was stabilized and in the intensive care unit at the Einstein hospital in Sao Paulo on Friday.

Dr. Luiz Henrique Borsato, who operated on the candidate, said the internal wounds were "grave" and "put the patient's life at risk" but that he was stable. Doctors were worried about an infection since Bolsonaro's intestines were perforated.

Bolsonaro likely needs to spend at least a week in the hospital and would be unable to campaign for at least three weeks - or just before the Oct. 7 first-round vote.

That could seriously damage his run.

Bolsonaro's tiny coalition has almost no campaign time on government-regulated candidate commercial blocs on television and radio. He must rely on social media and raucous rallies around the country to drum up support, events he is now unlikely to attend for some weeks.

Running as the law-and-order candidate, Bolsonaro has positioned himself as the anti-politician, though he has spent nearly three decades in Congress.

He has long espoused taking a radical stance on public security in Brazil, which has more homicides than any other country, according to U.N. statistics, and has openly praised Brazil's military dictatorship, which he has said should have killed more people.

Bolsonaro faces trial before the Supreme Court for speech that prosecutors said incited hate and rape. He has called the charges politically motivated.

His stabbing is the latest instance of political violence, which is particularly rampant at the local level. Earlier this year, Marielle Franco, a Rio city councilwoman who was an outspoken critic of police violence against slum residents, was assassinated.

One supporter camped outside Bolsonaro's hospital room, Bruno Engler, 21, who is running for a Minas Gerais state congressional seat on Bolsonaro's Social Liberal Party, said if he could, he would lynch the suspect.

"They call us on the right the intolerant, the violent ones, but those who are intolerant and violent are them," Engler said, referring to leftist voters.