Luiz Inacio Lula da Silva and Flavio Bolsonaro face off in Brazilian presidential election

Polls have opened across Brazil for a highly contested presidential election, pitting incumbent Luiz Inacio Lula da Silva against Senator Flavio Bolsonaro, son of former President Jair Bolsonaro.

A record 160 million registered voters are eligible to cast their ballots in Sunday's elections, which will also determine the fate of lawmakers, governors, and senators. The election is seen as a closely fought contest between Lula and Bolsonaro, with most opinion polls suggesting a narrow margin between them.

If no candidate secures more than 50 percent of valid votes, the top two contenders will proceed to a runoff on October 25. This scenario appears increasingly likely, given the tight race between Lula and Bolsonaro.

As voting got underway, Flavio Bolsonaro cast his ballot in Rio de Janeiro, expressing confidence that he would emerge victorious in the first round.

Brazil's presidential election has seen two vastly different candidates vying for power: Lula of the Workers' Party, who aims to continue his social programmes aimed at reducing inequality, and Bolsonaro of the Liberal Party, who has pledged a tough stance on crime and security.

Bolsonaro's campaign has also focused on his promise to strengthen ties with the United States under President Donald Trump. This pledge is particularly notable given the tensions between Washington and Beijing in their quest for global influence, with Brazil emerging as a key player in this competition.

The complexities of Bolsonaro's situation are underscored by the fact that his father, a former military officer, is currently serving a 27-year prison sentence for his role in a plot to overthrow Lula following his presidential loss in 2022. This has raised concerns about the state of Brazilian democracy and its ability to withstand pressures from within.

The election's high stakes have been underscored by comments from Al Jazeera's Lucia Newman, who reported from Sao Paulo that Bolsonaro is on a collision course with Trump, who has been a vocal supporter of Bolsonaro despite his own rivalry with Lula.

The presidential election in Brazil has been marked by deep-seated divisions between voters who support Lula's vision for the country's future and those who back Bolsonaro's more authoritarian approach.

Crime, insecurity, and living costs have dominated campaign discussions, with corruption and concerns about US intervention also playing a significant role. According to a recent survey, 31 percent of respondents cited violence as their top concern, followed by corruption at 20 percent and economic issues at 19 percent.

Lula's candidacy is seen as a symbol of Brazil's democratic progress since the end of its military dictatorship, while Bolsonaro's supporters argue that the country's institutions are weak and ineffective.