Nationwide demonstrations calling for the impeachment of President Dilma Rousseff have swept Brazil for the second day in less than a month.

Turnout at the latest protests appeared down, however, prompting questions about the future of the movement.

A poll published over the weekend suggested the majority of Brazilians supported opening impeachment proceedings against Ms Rousseff, whose second term in office has been buffeted by a corruption scandal at the nation's largest company, oil giant Petrobras, as well as a stalled economy, a sliding currency and political infighting.

Only 13 per cent of survey respondents evaluated her administration positively.

The protests, in cities from Belem, in the northern Amazonian rainforest region, to Curitiba in the south, were organised mostly via social media by an assortment of groups. Most were calling for Ms Rousseff's impeachment, but other demands ranged from urging looser gun control laws to a military coup.

In Rio, several thousand people marched along the golden sands of Copacabana beach, many dressed in the yellow and green of the Brazilian flag. The March 15 protest, by contrast, drew tens of thousands.

In the opposition stronghold of Sao Paulo, about 100,000 people marched on the city's main thoroughfare, according to an estimate by the respected Datafolha polling agency.

Antonio Guglielmi, a 61-year-old sales representative for a building materials company, said: "I will keep coming back to demonstrations like this one - big or small - because it is the best way for us to make our voices heard and demand an end to the Dilma government. The country cannot go on like this."

Much of the protesters' ire focused on the Petrobras scandal. Prosecutors say at least £550 million was paid in bribes and other funds by construction and engineering firms in exchange for inflated Petrobras contracts.

Ms Rousseff, a former chairwoman of Petrobras' board, has not been implicated and so far is not being investigated, though two of her former chiefs of staff are among the dozens of officials caught up in the inquiry.

One president, Fernando Collor de Mello, has been impeached since Brazil's return to democracy in 1985, but many legal experts have said that Ms Rousseff could be impeached only if evidence emerged directly linking her to crimes committed during her second term, which began in January.