A demonstrator rallies in support of Brazilian President Dilma Rousseff's impeachment in Sao Paulo on Sunday. (Miguel Schincariol/AFP/Getty Images)

Tens of thousands of Brazilians protested corruption and called for the impeachment of President Dilma Rousseff in demonstrations across the country Sunday. But the numbers were down from nationwide protests staged three times earlier this year.

This brought slight relief for Brazil’s embattled president as she struggles with a 10 percent approval rating, an economy expected to contract 4 percent this year and a corruption scandal in which billions of dollars were paid in bribes on contracts with Petrobras, the state-run oil company.

Rousseff’s former party treasurer and her government’s leader in Brazil’s senate have been jailed in connection with the scandal.

On Dec. 2, impeachment proceedings were opened against Rousseff in Brazil’s congress, under the accusation that she broke federal accounting laws. The Petrobras scandal was also cited.

But many Brazilians are uncertain about the proceedings, which were given the go-ahead by a controversial high-ranking politician who is facing corruption allegations.

The Rev. Severino Martini, 67, a Catholic priest, was among the protesters, many of whom were dressed in national colors, marching beside sound trucks on the Copacabana seafront in Rio. He said that he had voted for Rousseff’s charismatic predecessor, Luiz Inácio Lula da Silva, when the Workers’ Party first swept to power in 2002 — but that, like many Brazilians, he had lost faith because of the party’s corruption.

“They lied. It was all a facade. It was a project of power and domination,” Martini said. “I support impeachment.”

In São Paulo, 40,000 people marched, down from 135,000 in August, the Datafolha polling firm said. Numbers in Rio appeared significantly less than the 100,000 that organizers claimed attended a demonstration in March. There were protests Sunday in all 26 states and the capital, Brasilia.

Brazil’s contracting economy, with inflation running at 10 percent and unemployment rising, complicates Rousseff’s position.

Luan Alves, 22, working at a beach stall selling refreshments as the demonstration passed by, said he supported impeachment because of the economic crisis.

“Everything is getting more expensive; people are losing their jobs,” he said. “And next year, people say it will be worse.” It was Eduardo Cunha, speaker of Brazil’s Chamber of Deputies, who gave the impeachment process the go-ahead nearly two weeks ago.

In September, prosecutors revealed that Cunha and his wife held Swiss bank accounts that investigators believe he used to receive Petrobras bribe money. Earlier this year, Cunha told Congress he had no foreign bank accounts. On Sunday, the Folha de S.Paulo newspaper called in an editorial for his removal from office.

Demonstrators in Rio carried banners calling for his ouster as well as Rousseff’s. “It’s not enough to take Dilma out and leave him there,” said one protester, Fernando Cruz, 77. A few demonstrators called for military intervention for a three-to-four-year “cleanup” period.

There were chaotic scenes in Brazil’s congress last week after Cunha ruled that a vote to decide which deputies should sit on a commission to examine the impeachment request should take place in secret. Government deputies barred entrance to electronic voting booths, some of which were broken as scuffles occurred. A Supreme Court judge then suspended the vote.

Once the impeachment proceedings have passed the commission stage, two-thirds of the Chamber of Deputies have to vote in favor. Constitutional experts are divided on how the process should play out and what final role Brazil’s senate should play.

“A substantial part of the Brazilian population continues in favor of impeachment,” said José Álvaro Moisés, a political scientist at the University of São Paulo. “But the process has been very confused in the Congress. . . . Public opinion is not clear that it can happen.”

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