SAO PAULO — Brazilian President Luiz Inacio Lula da Silva on Sunday urged his supporters to reach out to voters who abstained from the Oct 4 first-round election as he seeks reelection in the presidential runoff scheduled for Oct 25.

"We have an obligation to talk to people who think they no longer have the right to vote," Lula told a rally in Sao Paulo, calling on supporters to encourage those who sat out the first round to cast their ballots in the runoff.

In the first round, Flavio Bolsonaro of the Liberal Party won 47.03 percent of the valid votes, ahead of Lula of the Workers' Party, who garnered 45.16 percent. The abstention rate reached 21.08 percent, the highest since 1998, with about 33.4 million eligible voters staying away from the polls.

According to the organizers, the rally brought together political leaders, government officials and representatives of organizations involved in education, science and technology.

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In his speech, Lula outlined priorities for a possible new term, including professional training in artificial intelligence, development of the digital industry, the energy transition and public security reform to combat organized crime.

Meanwhile, Flavio Bolsonaro also campaigned in Sao Paulo on Sunday, meeting with mayors and reelected Sao Paulo Governor Tarcisio de Freitas to consolidate political support ahead of the runoff.

A Datafolha poll released Thursday put Bolsonaro at 49 percent and Lula at 45 percent, a result within the survey's two-percentage-point margin of error. Another 5 percent of respondents said they intended to cast blank or invalid ballots, while 1 percent remained undecided.

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Since Brazil resumed direct presidential elections in 1989, no candidate who finished second in the first round has gone on to win the runoff. The 1.87-percentage-point gap between Bolsonaro and Lula in this year's first round was the narrowest recorded during that period.