Simone Tebet, centralist Brazilian senator, said she will be supported by leftist candidate Luiz Inacio Lula da Silva against far-right incumbent President Jair Bolsonaro, when the final vote takes place on October 30. Tebet has so far finished third in the presidential race.

In the first round on Sunday, Tebet garnered almost 5 million votes, rendering the candidate ineligible for the second round. 

She announced her support for Lula because of "his support for Brazilian democracy and the constitution."

Brazil braces for runoff; Lula da Silva to face Bolsonaro

The bitterly contested presidential election in Brazil will go to a runoff on October 30, with incumbent Jair Bolsonaro finishing a close second to front-runner Luiz Inacio Lula da Silva.

It was an unexpectedly strong result for Bolsonaro – and for Brazil's far-right, revealed in a number of key Congressional and governors' races.

Lula, Brazil's ex-president, who led the country from 2003 to 2010, was considered the favorite to win the race in a single round.

On the eve of the election, leading polling firm Datafolha predicted Lula would receive 50% of the vote, with Bolsonaro receiving 36%.

To win in the first round, a candidate needed to receive more than 50% of the vote. Instead, Bolsonaro, 67, and Lula, 76, will engage in tense elections.

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