With Brazil's presidential runoff election set for the 25th local time just a day away, incumbent President Luiz Inacio Lula da Silva (81), seeking a historic fourth term, and right-wing candidate Flavio Bolsonaro (45) remain locked in a tight neck-and-neck race within the margin of error until the very end.

According to foreign media reports including Reuters and AFP on the 24th, a presidential opinion poll released by the polling agency Datafolha showed Flavio Bolsonaro of the Liberal Party (PL) leading with 51% of the valid vote, edging out President Lula of the Workers' Party (PT), who registered 49%, by 2 percentage points.

Another survey by the polling institute Quaest also showed candidate Bolsonaro ahead of Lula by 2 percentage points.

However, the gaps in both polls remained within the margin of error of plus or minus 2 percentage points.

Candidate Bolsonaro emerged as a strong favorite after defying expectations by defeating incumbent President Lula in the first round of the presidential election on October 4.

Since democratization in 1989, no candidate who won the first round of a Brazilian presidential election has ever lost the runoff.

Bolsonaro gained momentum amid a recent wave of conservatism across Latin America, attacking the Lula administration's economic policy failures.

However, as President Lula's supporters rallied at the last minute ahead of the runoff, the outcome has become entirely unpredictable until the very end.

President Lula, vying for a fourth overall term, shows strength in the northeastern rural region, lower-income classes, Catholics, and voters with lower levels of education.

Lawmaker Bolsonaro holds the advantage in the southeastern region dense with large cities, the middle class, and evangelical Christians.

The showdown between these candidates is also highly significant as it reflects the direction of Latin America's "blue tide" (a wave of right-wing governments coming to power).

If candidate Bolsonaro achieves a final victory, Brazil, Latin America's largest economy, will join the blue tide following nations such as Argentina, Ecuador, Bolivia, Chile, Colombia, and Peru.

Voting in the Brazilian presidential election is conducted through an electronic voting system where voters press the number of their preferred candidate on voting machines.

Election results are expected to be announced within a few hours after polls close.

Incumbent candidate Bolsonaro's father, former President Jair Bolsonaro, raised allegations of election fraud regarding the electronic voting machines following his defeat in the 2022 presidential election, after which supporters staged massive riots refusing to accept the election results, storming the congress, supreme court, presidential palace, and government buildings.

Brazil's Federal Supreme Court sentenced former President Jair Bolsonaro to 27 years in prison last year on charges including conspiring with cabinet ministers to stage a military coup after losing the election, inciting his supporters to launch riots rejecting the election outcome, and involvement in a plot to assassinate President Lula.

Candidate Bolsonaro has pledged to immediately pardon his father if elected president.

(Photo: AP, Yonhap News)