Embattled Brazilian President Dilma Rousseff is looking to shore up the support of the parties that make up her governing coalition, news reports said Wednesday, a day after the country's largest party decamped in a move that will make it harder for Rousseff to fight impeachment proceedings against her.

Leaders of the Brazilian Democratic Movement Party, known as the PMDB, on Tuesday announced that party members would be immediately leaving their six Cabinet posts, as well as some 600 federal government jobs.

But it appeared Wednesday that at least three of the party's Cabinet ministers planned on staying in Rousseff's government. O Estado de S. Paulo daily reported Health Minister Marcelo Castro and Science and Technology Minister Celso Pansera wanted to cut a deal that would allow them to remain in the government, while Agriculture Minister Katia Abreu could sever her ties with Democratic Alliance in order to remain.

Rousseff was said to be planning to use the posts vacated by the Democratic Alliance to strengthen her support from the six parties that remain in the governing base, along with her left-leaning Workers' Party.

Rousseff needs to secure at least 172 out of 513 votes in the lower house of Congress to halt impeachment proceedings against her over allegations she violated fiscal rules. A vote on the matter is expected around mid-April, and without the PMDB's 69 votes, Rousseff's chances of surviving the vote appeared diminished.

Speaking at an event for the government's public housing scheme, Rousseff again lashed out at the impeachment process as an attempted "coup" against her, adding she hadn't committed any crime that would warrant her ousting.

"What we're discussing is impeachment without responsibility for a crime, and without responsibility for a crime, that's a coup," she said to a crowd of enthusiastic supporters who chanted: "There won't be a coup."

Rousseff has seen her popularity plummet amid the worst recession in decades and a sprawling corruption scandal at state-run oil giant Petrobras that has been moving closer to her inner circle. Rousseff, a former chairwoman of Petrobras' board, has not been implicated in the unfolding scandal at the oil company that prosecutors call the largest corruption scheme ever uncovered in Brazil.

A new opinion poll released Wednesday suggested just 10 percent of Brazilians have a favorable opinion of Rousseff. That's just slightly up from the single-digit approval ratings Rousseff faced last year, but still extremely low. The survey, by the Ibope polling agency, has a margin of error of plus or minus 2 percentage points. It was conducted from March 17-20, with 2,002 people interviewed nationwide.

Public disgust with politicians reaches far beyond Rousseff. Vice President Michel Temer, who is first in line to assume the presidency in case of impeachment, has been sullied by accusations he took part in the Petrobras corruption scheme, as have the two other figures in line to succeed Rousseff — the head of the Senate, Renan Calheiros, and the lower house, Eduardo Cunha. All three are with the Democratic Alliance and all deny any wrongdoing.

Also on Wednesday, the lower house's ethics committee met to discuss the case against Speaker Eduardo Cunha, who stands accused of lying to a parliamentary investigatory committee and risks being stripped of his mandate. Cunha told the committee he didn't have foreign bank accounts but Swiss documents later emerged linking him to accounts that prosecutors allege held money from Petrobras kickbacks.

On Tuesday, the judge in the Petrobras case, Sergio Moro, acknowledged he "may have erred" in making public tapped phone recordings of former President Luiz Inacio Lula da Silva, including a conversation with Rousseff. Moro released the recordings hours after Silva was appointed Rousseff's chief of staff earlier this month, prompting allegations of partisanship from the magistrate's supporters and critics alike.

Silva's appointment would have made it more difficult for Moro to look into allegations he may have benefited from the Petrobras scheme because Brazilian law requires the Supreme Court to authorize any investigation into Cabinet ministers. A justice on the top court prevented Silva from assuming the post.

In his written response to the Supreme Court, Judge Moro asked for "respectful apologies" for having made the recordings public, adding that he hadn't intended to "cause polemics or conflicts."