Anti-government demonstrators rally in Sao Paulo, Brazil. Thousands gathered to protest the government of President Dilma Rousseff and to call for her impeachment. (Bonnie Jo Mount/The Washington Post)

— Wearing national colors of green, yellow and blue, and brandishing flags and blowing horns and whistles, hundreds of thousands of protesters flooded cities across Brazil on Sunday to call for the impeachment of President Dilma Rousseff and an end to corruption. There were demonstrations in cities in all of Brazil’s states and its capital, Brasilia.

Earlier indications were that numbers were down compared with demonstrations in March and what was seen as dwindling protests in April. Later estimates, however, showed an increase on April’s crowds.

And while the political and economic crisis that has besieged the president since she began a second term in January continues to rage, there are signs that for now, at least, Brazil is drawing back from a clifftop decision to unseat a chief executive reelected less than a year ago.

Organizers had timed the protests to coincide with the 23rd anniversary of mass demonstrations that forced President Fernando Collor de Mello to resign in the face of a devastating corruption scandal. Sunday’s protesters again targeted the involvement of Rousseff’s Workers’ Party and its Congress allies in a multibillion-dollar corruption scheme at state-controlled oil company Petrobras.

But after intensive maneuvering, Brazil’s rebellious Congress now looks less likely to move toward an impeachment vote — and, unlike 23 years ago, numbers also suggested fewer Brazilians would support such a drastic move.

“The government is close to the brink and will continue close to the brink, but no one is willing to be that person who gives the final push,” said João de Castro Neves, Latin America director in the Washington office of an international political risk firm called Eurasia.

In Sao Paulo, the city’s central thoroughfare, Paulista Avenue, was taken over by tens of thousands of demonstrators — 135,000, according to an estimate by the Datafolha polling institute. The colorful, family atmosphere was more parade than protest, with music blasting from sound trucks, children carried on their parents’ shoulders and beer vendors moving among the crowds.

In 1992, Thays Heil, now 55, painted her face black for the anti-Collor protests. On Sunday she collected signatures for a petition in support of 10 anti­corruption measures proposed by federal prosecutors. “I am very ashamed of this government,” she said.

Rousseff faces two key potential impeachment threats: A federal court could vote to reject her government’s 2014 budget-account reports, alleging irregularities, while another court is considering a legal move by the opposition to revoke her mandate.

A key executive accused in the oil scandal who turned state’s evidence has alleged his company’s donations to her 2014 election campaign were bribes.

Although Rousseff has not been directly implicated in the Petrobras scheme, she was both minister of mines and energy and chairwoman of the Petrobras board. “Dilma is very responsible,” said Heil’s daughter Fernanda, 29, using the president’s first name, as is common in Brazil.

As the corruption scandal expanded, Rousseff’s approval rating plunged to 8 percent in an August poll. Dozens of politicians and high-ranking company executives are being investigated. Rousseff’s mentor, former president Luiz Inácio Lula da Silva, is also under investigation for influence peddling on behalf of construction giant Odebrecht, whose chief executive officer and other leading executives are jailed in connection with the Petrobras scandal.

“We cannot stand any more corruption,” said businesswoman Ana Rita Teixeira, 35, protesting with her daughter Giovanna, 13, on Paulista Avenue. Teixeira called for a new election but said she would not vote for the opposition Party of Brazilian Social Democracy, whose candidate Aécio Neves narrowly lost to Rousseff in last October’s election.

For the first time, Neves’s party endorsed these protests, and he spoke at a demonstration in Belo Horizonte. But his party’s closer involvement had not swelled numbers, nor has the protest movement defined more than a simplistic, negative agenda, said Rafael Cortez, a political scientist with a Sao Paulo consulting outfit, Tendencias. “It has not led to something more substantial,” he said.

In Brasilia, protesters held a minute of silence in front of Congress. Protests were held along the seafront in Rio de Janeiro and Salvador, and in Belo Horizonte, Recife and even the Amazon city of Belem. Others shunned the demonstrations, and 13,000 signed up for a Facebook counterprotest called “Have Sex on August 16.”

Rousseff has been able to strengthen her position in Congress by isolating the rebellious speaker of the House of Representatives, Eduardo Cunha, also under investigation in the oil scandal. His Brazilian Democratic Movement Party, her key Congress ally, is divided. Its leader, Michel Temer, who is Rousseff’s vice president, has called for unity. Rousseff’s government also embraced an “anti-crisis agenda” offered by another of its leaders, Senate president Renan Calheiros.

But Calheiros is also being investigated in connection with the scandal. “If Renan Calheiros’s name is indicted down the road, he will stop with his good-cop routine,” said Castro Neves.

In Sao Paulo, demonstrators were overwhelmingly white. “The majority of those who protest are upper-middle-class. It is not all Brazilians,” said Diego Rocha, 27, a black Brazilian selling jewelry on Paulista Avenue.

South America’s biggest metropolis is proud of its role as a motor of Brazil’s economy, currently in a recession with unemployment rising and inflation at almost 10 percent.

“The economy is getting worse,” said sales analyst Michelle Barbati, 31. She and her partner, Nelson Pessoa, 31, a tax consultant, were angry at the amount of money spent by the Workers’ Party on social welfare schemes in Brazil’s poorer northeast. “There is a lot of vote buying,” she said.

There has also been a growing realization that Brazil’s struggling economy would be hit further if Rousseff were impeached. An editorial in the O Globo newspaper argued that impeachment would increase the chances of Brazil losing its precious investment grade, already threatened.

“The business elites are thinking with their pockets,” Castro Neves said. And the political elite was thinking of its future. “If you force her removal without clear proof, it may even bring into question the legitimacy of the next government,” he said.

On Paulista Avenue, a minority called for military intervention and a return to the dictatorship that ran Brazil for two decades until 1985. “The number of interventionists has increased,” said Gerson Santos, 56. Later he addressed a small crowd from a sound truck beside a man in military fatigues who carried a shield and called himself “Captain Brazil.”

Further down the avenue, Daniel Castro, 20, an actor, watched proceedings with a frown. “I feel something very imposed, very authoritarian,” he said. “The way people are dealing with the situation is worrying.”

Nearby, Marcos Rett, 66, carried a placard with a photo of Sérgio Moro, the judge who has jailed dozens in the oil scandal. “We are in an era in which we look for a national hero,” he said. In troubled Brazil, a judge was the only one available.