The lower house is set to vote Sunday on whether to send the embattled president to face an impeachment trial in the Senate, an attempt Rousseff has called a "coup." It remains uncertain whether Vice President Michel Temer and Eduardo Cunha, speaker of the lower house, have the two-thirds majority needed to advance the impeachment proceedings.

Rousseff is accused of using an accounting trick to hide a budget shortfall in 2014, something she says was not illegal and a common practice in previous governments.

The proceedings also have to do with a corruption scandal linked to the state oil company Petrobras and a flailing economy, both of which have pushed her approval ratings down.

Rousseff is not directly linked to the corruption scandal, though Cunha, Temer and nearly half of Congress are.

Rousseff cancels rally appearance

The impeachment proceedings have divided the country.

Along Brasilia`s main boulevard leading to Congress, rival camps of demonstrators are camped out, separated by a 1-kilometer (0.6-mile) barricade.

Thousands of pro-government demonstrators arrived to hear Rousseff speak at the rally on Saturday, but her lobbying efforts meant she had to cancel her appearance.

Rousseff`s mentor, former President Luiz Inacio Lula da Silva, spoke to the crowd in her place, describing the impeachment effort as an attempt by the elites to roll back the gains of the Workers` Party.

"It seems to me that the Brazilian elite doesn`t like democracy," he told thousands of supporters. "When the poor started to climb up onto the social ladder, they were made uncomfortable."

In order for her impeachment to proceed to the Senate, two-thirds of the Chamber of Deputies` 513 members must vote to impeach. If Rousseff is impeached, Temer would take over.

A major rally is expected on Sunday.

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