From the day Jair Bolsonaro won Brazil's presidential election, leftist politicians and activists have begun lining up to oppose the changes in policy he was planning. Amid a polarized population, the rhetoric has been strong with perhaps the loudest voices coming from the defeated Worker's Party as CGTN's Paulo Cabral reports.

The leftist Worker's Party - PT - was defeated in the second round of Brazil's presidential election. But it won the biggest number of seats in the Chamber of Deputies: 56 of the 513 representatives. The party has vowed a staunch opposition to far-right President Jair Bolsonaro -- but in a parliament fragmented among 30 parties, it needs allies.

LUIZ DULCI VICE PRESIDENT OF WORKER'S PARTY "Our main task at this stage of Brazil's political life is to defend democracy and the political, social and economic rights of the population. And this goes much beyond the PT. To defend democracy, we need to form a very wide front and not only in the left wing but also with centrist forces who may want to join."

PROFESSOR CLAUDIO COUTO GETULIO VARGAS FOUNDATION "Of course in terms of the PT, the main opposition party, we have no doubt that the PT will be a very clear cut opposition to Bolsonaro. In terms of the other parties, like the Labour Democratic Party of Ciro Gomes and the Socialist Party, they perhaps will try to present themselves as a more moderate position but in terms of roll call votes, their congressional legislative behavior, they work in a very similar way to the more radical opposition."

Some of Bolsonaro's radical views could also run into opposition in sectors of center and even center-right parties, like Brazil's Social Democratic Party - PSDB. Former Sao Paulo governor Alberto Goldman - one of the party's most vocal critics of Bolsonaro - says a split in the PSDB cannot be ruled out.

ALBERTO GOLDMAN FORMER GOVERNOR OF SAO PAULO, PSDB "I think there is already a split in practice, that has just not been formalized. Many political figures of our party have already been announcing their support for the government, but for now in a personal capacity. The party itself doesn't have a clear path yet."

PAULO CABRAL SAO PAULO "Opposition to President Jair Bolsonaro will not be limited to political parties. Leftist social and activist movements- often antagonized by the former army captain - already promise to resist the new administration."

The Landless Workers Movement is one of them. It's a militant group that occupies private but unused farmland for distribution to landless peasants. During the campaign, Jair Bolsonaro said he would seek legislation to deem such occupations terrorism - and vowed to oppose all kinds of activism in Brazil.

GILMAR MAURO NATIONAL COORDINATOR OF LANDLESS WORKERS MOVEMENT "This is a neo-fascist government which is opposing and trying to criminalize the left wing and the popular activist movements. So, I have no doubt there will be resistance. Student organizations for example will resist and also the landless and homeless movements and trade unions."

Bolsonaro achieved a clear victory in the presidential election, in a deeply polarized political environment despite running an anti-establishment campaign with only the support of small political parties. The opposition is vocal. The coming months will reveal whether it's also strong enough to block the new president from implementing his controversial agenda. Paulo Cabral, CGTN, Sao Paulo.