Brazil’s former leader Luiz Inació Lula da Silva has kickstarted what he hopes will be a sensational finale to one of Latin America’s most extraordinary political careers, publicly declaring his intention to challenge Jair Bolsonaro for the presidency and urging citizens to unite against the far-right populist’s “incompetence and authoritarianism”. Speaking at a rally in São Paulo, where the one-time lathe operator began his spectacular rise to power as a union leader more than four decades ago, Lula publicly spelled out his ambition to reclaim the presidency for the first time. “I am certain that we are going to manage to stage the greatest peaceful revolution the world has ever seen,” the 76-year-old leftist told thousands of supporters, who had gathered for the launch of what Lula called a cross-party anti-Bolsonaro alliance called Vamos Juntos Pelo Brasil, or Let’s Pull Together for Brazil. “We have a dream. We are moved by hope – and there is no force greater than the hope of a people who know they can be happy once more … Once again we are going to care for Brazil and the Brazilian people,” Lula said. The seats before him were filled by a who’s who of the Brazilian left, as well as celebrities, intellectuals, union leaders and grassroots activists who had travelled from all across the country – united in their desire to stop Bolsonaro returning to power when nearly 150 million Brazilians choose their next leader in October. “Bolsonaro represents the death of our people, our extermination … Lula’s the opposite – he represents hope,” said Nathália Purificação, 23, an Afro-Brazilian activist from Bom Jesus da Lapa in the north-eastern state of Bahia. Ademario Nogueira, a 58-year-old campaigner from the capital, Brasília, brandished a portrait of his bearded leader. “He’s the horseman of hope,” Nogueira said of Lula, a two-term president from 2003 to 2010 who was barred from the 2018 election after being jailed on controversial corruption charges that were annulled last year. Opinion polls suggest Lula is on course to win his sixth presidential run since he first tried to become the leader of South America’s largest democracy in 1989. One survey, released on the eve of Lula’s announcement, gave him a 13% lead over Bolsonaro in the first round and a 20% lead in a second round runoff. Sixty per cent of voters said they would not vote for Bolsonaro – who is widely blamed for mishandling a Covid outbreak that has killed nearly 665,000 citizens – under any circumstance. More than 60% believe the economy is going in the wrong direction, with rising inflation, high unemployment and a growing cost of living crisis. “It’s Lula’s to lose, clearly,” said Felipe Nunes, the head of the polling group Quaest. Even so, in recent weeks there have been signs of nervousness among Lula allies and progressive Brazilians desperate to see the back of Bolsonaro, after a series of unforced bloopers from the veteran leftist. Last weekend Lula was forced to apologise after suggesting police officers were not human beings. This week he was criticised for claiming the Ukrainian president, Volodymyr Zelenskiy, and his Russian counterpart, Vladimir Putin, were equally to blame for the war there. “If Lula carries on with this verbal incontinence … he’ll give the current occupant of the presidential palace a serious shot at re-election,” the Brazilian author Paulo Coelho warned on Twitter. Some critics complain Lula has failed to offer a clear vision for the future and is relying too heavily on rekindling nostalgia over his two-term presidency, when a global commodity boom helped him pump vast sums into poverty reduction schemes and infrastructure projects. In an interview with Time magazine, published on the eve of Saturday’s event, Lula declared: “Instead of asking what I will do, just look at what I have done”. Those accomplishments – which included helping millions escape poverty and expanding access to education – were given centre stage at Saturday’s event in São Paulo, the city to which a 10-year-old Lula moved in 1955, three years after his family fled rural hardship in the north-eastern state of Pernambuco. The auditorium was plastered with photographs remembering Lula’s years in power. Before his speech, videos were shown in which he appeared alongside global figures such as Barack Obama, George W Bush and Queen Elizabeth. “He’s the best president in the history of Brazil,” said Nogueira, an activist from Lula’s Worker’s party (PT). “Brazil is desperate to be happy again.” Lula, who was freed up to run in the 2022 election after the supreme court annulled his convictions, told supporters that at the coming election Brazil would have the chance to decide which country it wanted to be. “The Brazil of democracy or authoritarianism … The Brazil of knowledge and tolerance or the Brazil of obscurantism and violence, of education and culture or of revolvers and rifles.” “It has never, ever been so easy to choose,” Lula added with a smile. “And never has it been more important to make the right choice.” Also on show was Lula’s attempt to build a broad coalition capable of defeating Bolsonaro, including parties from outside the left. Lula’s running mate, the centre-right former São Paulo governor Geraldo Alckmin, was unable to attend after contracting Covid but in a video message told the audience that unity was essential to protect democracy and defeat “the most disastrous and most cruel government in Brazilian history”. Juliano Medeiros, the president of the leftwing Socialism and Liberty party (PSOL), said it was essential for the opposition to coalesce, as it failed to do before Bolsonaro’s shock 2018 election. The anti-Bolsonaro movement also urgently needed to ensure the 2022 campaign was based on exposing Bolsonaro’s failures and the real economic problems facing Brazil’s 215 million citizens. “In 2018 it was Bolsonarismo and the far right that set the agenda: it was all about anti-communism and corruption and culture wars. This time our challenge is to put unemployment, inflation, hunger and equality at the centre of the debate,” Medeiros said, as delegates streamed into the convention centre. Activists voiced optimism that Bolsonaro’s days in power were numbered. “I don’t have the words to describe my happiness,” said Susy Keith, a 45-year-old producer from Rio who was dressed as a bright red star. However, many progressives feel profound trepidation over the coming months, with Brazil’s pro-gun president billing the election as an epochal struggle between ultraconservative “good” and the “evil” left. “My main worry is violence. I think there’s a real chance we will see fighting in the streets. These are going to be the most polarised elections on Earth,” said Celso Rocha de Barros, a columnist for the Folha de São Paulo newspaper. On Saturday Lula urged supporters to resist provocation during the campaign and to face their opponents with love, not hate. “We are going to win this battle for democracy with smiles, affection, love, peace and harmony,” he said.