Daniel Gallas
BBC Brasil

Earlier this month, Brazilians went to the polls and gave Flavio Bolsonaro a first-round lead of 2.2 million votes over Luiz Inácio Lula da Silva.

But three weeks later, Lula won the presidency by a margin of four million votes. The scale of the turnaround was remarkable. Between the two rounds, Lula gained around 11 million additional votes.

So, how did he do it? Three factors help explain:

• First, turnout increased. More than 2.3 million additional voters cast ballots in the second round compared with the first
• Second, Lula appears to have won over many voters who either abstained or declined to back a candidate in the first round. The number of blank and spoilt ballots fell by about 1.8 million
• Third, he succeeded in persuading some voters who had previously backed Flavio Bolsonaro or other candidates to switch sides

Ione Wells
Reporting from Brasília

Image source, Reuters

Things felt tense here in the capital, Brasilia, after the results came in and Flavio Bolsonaro rejected the result.

There are concerns about whether this could trigger unrest with his supporters. Many remember the scenes of his father Jair Bolsonaro’s supporters storming government buildings and the Supreme Court here ahead of Lula’s 2023 inauguration after they did not recognise the last election result.

So far, things are calm here.

And there are a few differences to 2022's result that suggest it would be harder to try something similar.

Firstly, I remember covering Bolsonaro senior's coup trial here last year and it was striking how much the evidence revealed about how he tried to use the machinery of the state – and senior figures within it – as president, to cling on to power. Because President Lula is the incumbent this time, Flavio Bolsonaro can't try that.

Secondly, this result was not as close as 2022, so it would be a lot harder to claim irregularities.

While Bolsonaro shares a lot of his father's traits, he has framed himself as the more "moderate" Bolsonaro, the "vaccinated" one even – so would he really go there? He has seen the consequences such rhetoric and actions had for his father.

How the next few days play out will be key.

Ione Wells
Reporting from Brasília

Image source, AFP via Getty Images

To give you a sense of how social media mobilised Lula's base ahead of the second round – one WhatsApp group that translates as "Lula’s army" had nearly 11 million followers.

It was used in the build-up to the final vote to share information about his campaign, mobilise supporters to turn out, and share news and updates.

To give a sense of scale, about 124 million people voted for Lula or Bolsonaro in this election.

I met many supporters of Lula's in the last week at demonstrations who specifically mentioned this group, and the president himself said he'd never seen anything like the campaign that had happened in the last few weeks.

Madeleine Lake
Live reporter

Image source, Reuters

The winner: Brazil's left-wing President Luiz Inácio Lula da Silva has won a fourth term in office, defeating his right-wing challenger Flávio Bolsonaro.

What was the margin? Lula won 51.79% of the vote, while Bolsonaro had 48.21% - that's a difference of more than 4 million votes. It's also a historic bounce back after Lula lost the first round of voting.

The defeated candidate: Flávio Bolsonaro has not taken the loss lightly, he's called for the result to be annulled and said it was "impossible to recognise". For his supporters, it's been a devastating blow.

Lula's victory was far from certain: Lula was in second place at 45% during the first round on 4 October, while Bolsonaro was ahead at 47%. Lula went from second to first place in 211 municipalities between the two rounds.

Silence from Washington so far: there's been no word yet from US President Donald Trump after he said he would be watching the elections. Our Global affairs reporter Mimi Swaby explains that Bolsonaro had US backing

Stick with us as we bring you the voices from voters and analysis from our correspondents.

Left-wing President Luiz Inácio Lula da Silva defeated his right-wing rival Flávio Bolsonaro in the presidential election run-off overnight.

In the first round on 4 October, Bolsonaro had won with 47%, falling short of an outright majority and triggering the second round. In yesterday's voting, Lula came out on top with 51.79% as you can see from the graph below:

Lula won in just under half of the 27 Brazilian states:

Image source, Getty Images

Born into a poor family in 1945, Lula sold peanuts as a child, only learning to read aged 10.

He became a metal worker in his teens, losing a finger in an industrial accident in the 1960s.

His political journey started in the trade union movement, where he was elected head of Metalworkers' Union in 1975. Five years later, he founded the Workers' Party (Partido dos Trabalhadores or PT) - Brazil's first major socialist party.

It took him more than two decades to win the presidency, which he first did in 2002.

Lula made social equality a central plank of his early premiership, funnelling billions into grant programmes like the Bolsa Familia.

He was jailed in 2018 following a huge bribery scandal, dubbed Operation Car Wash, and served more than 18 months.

His convictions were overturned by a Supreme Court Judge in 2021, allowing him to run for and secure a third term as president in 2022.

Image source, Getty Images

Social media has played a significant role in Brazil's presidential elections.

On Tuesday, Meta's oversight board, external said it had found "enforcement failures" in the moderation of content relating to Brazil's presidential election.

The statement followed allegations by President Lula's campaign team, which says the company – which owns Facebook, Instagram and WhatsApp – had favoured Bolsonaro.

The oversight board found Meta had excessively used anti-fraud policies against Lula's ad accounts. The failure, the body says, "should have been escalated to an internal team of expert reviewers".

Meta has rejected claims of political bias.

Image source, AFP via Getty Images

Right-wing senator-elect Marcel Van Hattem is a close ally of Flávio Bolsonaro and was in the room with him when the results were declared.

"He was upset, but I think he was much more than upset," Hattem tells BBC World Service's Newsday programme.

He says Bolsonaro had a sense of "indignation" about the Supreme Court's decision to extend voting by two hours. As a reminder, both sides requested extensions to voting hours for different reasons – read more here.

Hattem says he would like to see the whole election run again, and pushed back on the idea that this could be undemocratic or motivated by unhappiness with the result.

Electoral law experts contacted by BBC News Brasil say the chances of the election being annulled are remote.

Image source, Bloomberg via Getty Images

In the first round of voting - on 4 October - President Lula came in second place with 45%, behind Flávio Bolsonaro, who received 47%.

The 2.2 million vote difference in favour of Bolsonaro gave way to a 4.4 million vote advantage for Lula in the second round.

These were some of the key shifts behind Lula's victory:

• The state of Minas Gerais, in Brazil's south-east, flipped from Bolsonaro to Lula from the first to the second round of voting – it was the only state to do so
• In north-east Brazil, Lula expanded his percentage in all nine states, with Bahia showing the largest increase
• Between the two rounds of voting, Lula also went from second place to first place in 211 municipalities including in two state capitals: Rio de Janeiro and Macapá

Image source, EPA/ Shutterstock

World leaders are still sharing their reactions to Lula’s win, here’s the latest we’ve seen:

• President of Pakistan Asif Ali Zardari posted on X saying he was confident that the "longstanding friendly relations" between Pakistan and Brazil would grow
• India's Prime Minister Narendra Modi says he looks forward to "working closely" with Lula, adding the leaders will "advance the shared priorities of the Global South and work towards a more inclusive, equitable and sustainable world"
• Canadian Prime Minister Mark Carney says the relationship between his country and Brazil has already "flourished under our partnership", and he adds that he hopes to create new trade opportunities and protect the environment
• South Africa’s President Cyril Ramaphosa says Lula's victory is "a victory for the global south and progressive forces throughout the world"
• Ecuador President Daniel Noboa Azin also congratulates Lula, saying the region has "common enemies, shared challenges, and much to gain when we work together"

You can read more about how other Latin American leaders have reacted to the victory here.

Image source, Getty Images

While Lula's supporters are ecstatic about his victory, the result shows that the country remains deeply divided, with more than 48% of voters choosing Bolsonaro.

In addition to the challenge of uniting such a deeply polarised country, Lula will have to govern alongside the most right-wing Congress in Brazil's democratic era.

Before the election, Lula promised to bridge the gap between Brazil's opposing political poles with "a new way of governing", adding in a WhatsApp livestream before the election that "this country will never be the same again".

While he provided little detail as to what the new way of governing would entail, he insisted he would "remain firm in the fight for a more just country, with opportunities for all and policies directed at the needs of the population".

With a largely hostile Congress, this fight just may prove much harder for the veteran leader - who will be 85 by the end of his fourth term - than in his three previous terms in office.

• Read more about the challenges Lula faces in our news story

As we have been reporting, President Luiz Inácio Lula da Silva earlier addressed his supporters in São Paulo and thousands could be seen cheering and celebrating in the streets.

Meanwhile, it was a different story for supporters of Flávio Bolsonaro, the son of the former president Jair - who has so far refused to recognise Lula's victory.

Image source, Reuters

Image source, EPA/ Shutterstock

Image source, Reuters

Image source, Reuters

Image source, Reuters

Leaders across Europe have been waking up to the news of Lula’s victory and sharing their reactions.

EU chief Ursula von der Leyen congratulates President Lula, saying that "democracy and multilateralism have won in Brazil".

She says Europe's partnership with Brazil is thriving and the countries will work for open trade, strong climate ambitions and a "rules-based order".

French President Emmanuel Macron says France and Brazil have "much to build together" and should work "in service of a more just world".

Spanish Prime Minister Pedro Sánchez calls it a "great victory," saying "the comeback of global progressivism has just begun", adding: "What has happened in Brazil will happen in Spain”.

Justin Rowlatt
Climate editor

Image source, Reuters

Satellite data from Brazil’s space agency, INPE, which has tracked Amazon clear-cutting since 1988, shows 3,335 km² (1,287 square miles) cleared in the year to July, 42% less than the year before.

It is a dramatic turnaround.

Lula’s predecessor was Jair Bolsonaro, father of Flávio, his opponent in Sunday’s runoff.

Bolsonaro pushed to open the Amazon to development, weakened the Ibama environmental agency and fired INPE’s director after disputing its data.

Clearing during his administration totalled nearly 45,600 km², against about 24,600 km² under Lula, according to INPE data. Environmental groups credit restored enforcement for much of the decline.

Flávio Bolsonaro had pledged to end illegal deforestation by 2029 but offered little detail on how he would achieve it.

The decline slows the loss but does not stop it.

Since satellite monitoring began in 1988, an area of Amazon rainforest approaching the size of Spain has been cleared.

Image source, Bloomberg via Getty Images

Speaking from outside his home in Brasília after the election result was called, opposition candidate Flávio Bolsonaro, who had won the first round, refused to recognise Lula's victory in the run-off vote.

He told his assembled supporters that the result was "impossible" and "inexplicable".

Bolsonaro is calling for an annulment of the election, saying that "the rules of the game were changed" - referring to the decision of the Supreme Court to extend voting by two hours.

Before the result was declared, both sides had asked for extensions to voting hours, for different reasons.

Electoral law experts contacted by BBC News Brasil say the chances of the election being annulled are remote given, for example, Lula's margin of victory by 4.4 million votes.

Vanessa Buschschlüter
Latin America editor

Image source, Getty Images

Luiz Inácio Lula da Silvahas been president three times already.

When he started his third term in office in 2023, he vowed it would be his last, and yet his party endorsed him as their candidate again this year, even though he will turn 81 two days after the election.

Even backers of his party will acknowledge that he achieved more in his first two terms – from January 2003 to December 2010 – than in this most recent four years in office.

He was widely praised for lifting millions out of poverty with the help of a cash-transfer programme called Bolsa Família and left office on 1 January 2011 with record approval ratings of over 80%.

But his political career suffered serious setbacks in the following years – he was convicted of corruption and sent to jail for more than 18 months.

Those convictions were annulled in 2021, leaving Lula free to run for the presidency in the 2022 election, in which he beat Jair Bolsonaro.

There is no doubt he remains a towering figure in the left. But while his supporters described him ahead of the 2022 election as the "saviour of the Amazon", praising his commitment to protecting the rainforest, some environmentalists have been critical of some of his recent actions.

His support for exploratory oil drilling in offshore waters near the mouth of the Amazon in particular has drawn criticism.

Lula insists that he remains committed to eventually phasing out fossil fuels and argues that oil revenues are key to financing Brazil's transition to clean energy.

Mimi Swaby
Global affairs reporter

Image source, Getty Images

We have yet to hear Donald Trump's reaction to the election result. There was no secret that Senator Flávio Bolsonaro had US backing, following in the footsteps of his father Jair Bolsonaro.

Lula defeating Flávio Bolsonaro keeps Latin America's biggest economy at odds with Washington.

Flávio Bolsonaro campaigned on an iron fist tackling crime. It's not a new strategy. It's part of a playbook we have seen across Latin America which has voted in a string of right-wing leaders on this very promise. All strong allies of Donald Trump.

One of Bolsonaro's pledges if he won was that Brazil would join the Shield of the Americas, a US-led security initiative against so called "narco-terrorism". A term echoed by Bolsonaro junior on the campaign trail.

Flávio Bolsonaro met with Trump in May at the ​White House to shore up support as scandal ‌dented his popularity with voters.

And Washington has played a heavy hand in the Brazilian politics. Its policies included designating Brazilian gangs as terrorist groups and ​imposing sanctions against the Brazilian Supreme Court Justice who spearheaded the investigation into Jair Bolsonaro.

Former right-wing leader Jair Bolsonaro is serving a 27-year prison sentence in connection with a coup attempt after his re-election loss in 2022.

Branca Lessa de Sa
Reporting from Brasília

During his victory speech in São Paulo, Lula thanked a congressman named André Janones for his "exponential" role in the campaign. But who is Janones?

The 42-year-old politician from Minas Gerais is the founder of a viral Whatsapp channel named "Lula's Army", and has led a highly organised and effective online campaign in support of the president.

The Whatsapp channel became one of the Lula campaign's main digital mobilisation tools in the last few weeks, aiming to circulate content favourable to the president.

In regular videos and messages, Janones would urge participants – who he referred to as "soldiers" – to share posts and invite new members. Shortly before the runoff this Sunday, the channel surpassed ten million followers.

In his speech in São Paulo, Lula said that this election had taught him many lessons; among them, the power of social media.

"I want to tell you all that we will allow people to participate more in our decision-making, and that digital communication will play a big role in my new government," he said.

Image source, Reuters

If you're just joining us, here's a recap of how the run-off vote in Brazil's presidential election unfolded:

• Brazil's incumbent left-wing president Luiz Inácio Lula da Silva defeated his right-wing rival Flávio Bolsonaro, overturning a defeat in the first round of voting
• According to Brazil's Superior Electoral Court, Lula secured 51.79% of the votes, compared with Bolsonaro's 48.21% - a difference of more than 4 million votes
• Lula's victory is the first time since Brazil's return to democracy in 1988 that a candidate who lost the first round has gone on to win the presidency
• Lula thanked his supporters who he said had "defended Brazilian democracy" - he also said the result showed Brazil "will not accept being anyone's backyard"
• Bolsonaro said the result was "inexplicable" and has called for it to be annulled - though Brazil's Supreme Court president has confirmed the result and analysts tell the BBC the chances of an annulment are remote
• Voting was extended by two hours after a request from both campaigns. Lula's team alleged voter suppression due to a shortage of buses in several cities and Bolsonaro's team raised concerns about poor weather conditions in the south of the country

Vinícius de S. Mendes
BBC News Brasil, in São Paulo

Image source, Reuters

Flávio Bolsonaro has called for the election result to be annulled, but the chances of this happening are remote, according to electoral law experts contacted by BBC News Brasil.

Fernando Neisser, en electoral law expert at the Institute of Lawyers of São Paulo (Iasp), said that it would be "difficult from a legal standpoint" and would depend on the "narrative" his lawyers put forward.

He added that since the margin of votes between the two candidates was relatively large - with Lula getting 4.4 million votes more than Bolsonaro - it seemed unlikely there would be an annulment.

An added complication is that the dates of the presidential election in Brazil are fixed and determined by the constitution, says electoral law expert Alberto Rollo.

"We can't change the constitution. We can't say say 'it didn't count, we'll do it next week, or on 15 November, or 30 November'," he told BBC News Brasil.

Several of the experts consulted said that fact that the Bolsonaro camp had officially requested that voting be extended would make it hard for them to now use the extension as grounds for an annulment.