Low turnout at pro-impeachment rallies on Sunday provided some respite for President Dilma Rousseff but the real test of the popular mood will come when Brazil returns from its summer holidays in March to face a deepening recession and fewer jobs.

The tepid turnout at the weekend protests were a welcome break for the unpopular Rousseff ahead of crucial decisions in Congress and the Supreme Court this week that will decide the course of the proceedings against her.

With the Catholic country winding down for Christmas, organizers said they had no time to rally people onto the streets after the proceedings against Rousseff were launched this month.

Datafolha polling firm estimated that 76,000 people joined protests in Brazilian cities on Sunday, compared with more than 5,00,000 in August and April, and 1.7 million in March.

Organizers dubbed Sunday's protests a warm-up for bigger demonstrations scheduled for 13 March.

Political analysts say the impeachment process has so far failed to capture Brazilians' imagination because the man who launched it, House Speaker Eduardo Cunha, has been discredited by corruption charges hanging over him.

Rousseff is charged with breaking spending rules to bolster her re-election bid last year.

"No one is leading the impeachment movement, and it won't take off until people see that impeachment can actually change things and popular pressure makes a difference," said Rafael Cortez, analyst at the Tendencias consulting firm.

Officials in Rousseff's weakened government were happy to see smaller crowds, especially in the poor Northeastern region of Brazil, a bastion of support for her Workers' Party. Protests there were negligible on Sunday.

But the government is worried that could change after Carnival in February if the economy continues to decline, depressed further by the paralysis of a political crisis, a presidential aide said.

With the jobless rate running at a six-year high of 7.9%, many people who lost their jobs in 2015 will see unemployment benefits expire in the coming months, raising the temperature on the streets.

That is why Rousseff and her dwindling supporters in Congress are keen to see impeachment put to a vote quickly on the floor of the house.

The Supreme Court on Wednesday must rule on a government request to annul the impeachment process. The top court must also decide whether the Senate, where Rousseff's position is stronger, can vote to shelve the proceedings.

The court enters recess on Friday until February. If it clarifies the rules of the process this week, Congress could be recalled from its summer recess in January to vote on impeachment.

In the meantime, Cunha could lose his seat if the house ethics committee, which meets on Tuesday, decides to investigate him for lying about bank accounts in Switzerland.

Despite a split with her main coalition ally, the Brazilian Democratic Movement Party (PMDB), Rousseff is believed to still have enough support to block impeachment with one-third of the lower chamber.

If she loses in the house, the Senate takes up the impeachment process, and there she is more likely to prevail, according to Senator Eunicio Oliveira, the PMDB's leader in the Senate.

"The PMDB is very divided, 50-50, over her impeachment, but in the Senate she has a majority," he said by telephone.

Oliveira said economic crisis had undermined Rousseff's popularity but "Brazilians are beginning to see she has not committed a crime that warrants her removal from the palace."