RIO DE JANEIRO: Luiz Inacio Lula da Silva, who started out a shoeshine boy and became the most popular president in Brazilian history, has racked up a lifetime of improbable victories.

Now, as he eyes a run against far-right President Jair Bolsonaro next year, the 75-year-old leftist leader is seeking another: win back the political center that abandoned him in disgust when he was jailed for corruption in 2018.

It is still early to predict the October 2022 election, but polls show it shaping up as a Bolsonaro-Lula showdown, likely headed for a runoff.

That means the next leader of Latin America's largest economy may well be decided by a battle for the grudging votes of the more than one-third of Brazilians who intensely dislike both.

Pulling off a presidential comeback would be nothing short of astounding for Lula, whose towering legacy collapsed when he was convicted of taking bribes -- part of a massive investigation into a multi-billion-dollar corruption scheme involving state-run oil company Petrobras.

But it would not be the first surprise from the former steelworker and union leader, who rose from poverty to become a two-term president from 2003 to 2010, leading Brazil through a transformative boom.

To pull it off, the charismatic but tarnished veteran would have to win back at least some of the middle-class voters and business elites who punished his Workers' Party (PT) at the polls in 2018.

In a deeply polarized Brazil, Lula is striving to sell himself as a moderate to the alienated middle.

"Lula is a versatile animal who has gone back and forth over the past four decades, from far-left in the 1980s to a centrist partnering up with conservatives" in the 2000s, said political scientist Oliver Stuenkel of the Getulio Vargas Foundation.

"Now he's back in governing mode," he told AFP.

"He's clearly positioning himself more as a centrist."