Brazil's biggest cities, Sao Paulo and Rio de Janeiro, began electing their next mayors Sunday as the country held municipal runoffs, the last polls before far-right President Jair Bolsonaro is up for reelection in 2022.
In Sao Paulo, Brazil's economic capital, centrist incumbent Bruno Covas faces leftist challenger Guilherme Boulos, a leader of the Homeless Workers' Movement (MTST).
Boulos, 38, who is running for the upstart Socialism and Liberty Party (PSOL), trails in the polls by about 10 points.
But he has momentum: he came from behind in the first round on November 15 to beat both Bolsonaro's candidate and a leftist rival from the more-established Workers' Party (PT).
Young and charismatic, he is being called the new face of the Brazilian left, which is still reeling from the 2016 impeachment of President Dilma Rousseff and the jailing of ex-president and PT founder Luiz Inacio Lula da Silva on corruption charges.
The runoff took a twist two days before the vote when Boulos announced he had tested positive for the new coronavirus, forcing the cancellation of the candidates' final debate.
Covas, a cancer survivor, meanwhile has a powerful backer in Sao Paulo governor Joao Doria, his predecessor and mentor, a top contender to challenge Bolsonaro for the presidency.
In June, Covas was also diagnosed with coronavirus.
The virus has indelibly marked the municipal elections in the giant country of 212 million people.
The polls were postponed by six weeks because of the pandemic, with the period between the first and second rounds reduced from four weeks to two.
The authorities are urging voters to bring their own pens, respect social distancing guidelines and disinfect their hands multiple times.
Bolsonaro, who has downplayed the virus as a "little flu," faces criticism for his handling of the pandemic, which has killed more than 172,000 people in Brazil -- the second-highest death toll worldwide, after the United States.
In Rio de Janeiro, Brazil's second city, opinion polls indicate incumbent Mayor Marcelo Crivella, an Evangelical pastor and Bolsonaro ally, is set to lose in a landslide to ex-mayor Eduardo Paes of the traditional right-wing Democrats party (DEM).
Other races to watch include the northeastern city of Recife -- scene of a family feud on the left between cousins Joao Campos of the center-left Brazilian Socialist Party (PSB) and Marilia Arraes of the PT -- and the southern city of Porto Alegre.
There, another rising left-wing star, Manuela D'Avila of the Communist Party of Brazil, faces centrist candidate Sebastiao Melo, in a city rocked by violent protests following the first-round vote after two white security guards killed a black customer at a supermarket.
In all, 57 cities across Brazil are holding mayoral runoffs.
Results are expected from around 0100 GMT Monday.