Ms. Rousseff, then, is something of a rarity among Brazil’s major political figures: She has not been accused of stealing for herself.

Eduardo Cunha, the powerful speaker of the lower house who is leading the impeachment effort, is going on trial at the country’s highest court, the Supreme Federal Tribunal, on charges that he pocketed as much as $40 million in bribes. Mr. Cunha, an evangelical Christian radio commentator and economist who regularly issues Twitter messages quoting from the Bible, is accused of laundering the gains through an evangelical megachurch.

Vice President Michel Temer, who is expected to take over if Ms. Rousseff is forced to step aside, has been accused of involvement in an illegal ethanol-purchasing scheme.

Renan Calheiros, the Senate leader, who is also on the presidential succession chain, is under investigation over claims that he received bribes in the giant scandal surrounding the national oil company, Petrobras. He has also been accused of tax evasion and of allowing a lobbyist to pay child support for a daughter from an extramarital affair.

Image Vice President Michel Temer, who is expected to take over if Ms. Rousseff is forced to step aside, has been accused of involvement in an illegal ethanol-purchasing scheme. Credit... Adriano Machado/Reuters

Altogether, 60 percent of the 594 members of Brazil’s Congress face serious charges like bribery, electoral fraud, illegal deforestation, kidnapping and homicide, according to Transparency Brazil, a corruption-monitoring group.

The issue has even become a part of the president’s defense strategy. In particular, Ms. Rousseff and her supporters have argued, how can the impeachment process be directed by someone who is going on trial for corruption himself?