BRASILIA (Reuters) - A Brazilian appeals court on Tuesday said it would decide on Jan. 24 on an appeal by former President Luiz Inacio Lula da Silva against a corruption conviction that could bar him from running in the 2018 presidential race.

FILE PHOTO: Former Brazil's President Luiz Inacio Lula da Silva speaks during a national congress of Communist Party of Brazil in Brasilia, Brazil, November 19, 2017. REUTERS/Ueslei Marcelino

Despite the conviction and four other charges of corruption, the leftist icon and former labor union leader remains Brazil’s most popular politician and is leading early opinion polls ahead of next year’s poll.

Brazil’s benchmark Bovespa stock index rallied on the news, first reported on the website of newspaper Folha de S.Paulo, to close 1.4 percent higher.

Investors had been wary that a delay in the appeals court decision until later next year would give Lula more time to consolidate himself as the front-runner in the campaign, making it harder for judges to bar his candidacy.

Lula’s lawyers criticized the “record” speed at which the appeals process was being brought to a decision.

If the TRF-4 regional appeals court in Porto Alegre upholds the conviction, Lula can appeal to higher courts, but he would be blacklisted and unable to run for office.

A Datafolha survey published on Dec. 2 showed Lula gaining at least 34 percent of the votes if the election were held today, double the support for his nearest rival. It also showed him winning a runoff against likely contenders, Sao Paulo Governor Geraldo Alckmin, far-right Congressman Jair Bolsonaro or environmentalist Marina Silva.

Lula was Brazil’s first working-class president and millions of Brazilians were lifted from poverty by social programs introduced during his two terms in office from 2003-2010.

His handpicked successor Dilma Rousseff was impeached last year for breaking budget laws, ending 13 years of rule by Lula’s Workers Party. Critics say his legacy was Brazil’s worst economic recession and its biggest corruption scandal.

Lula was sentenced in July to nearly 10 years in jail for accepting 3.7 million reais ($1.1 million) in bribes from an engineering firm in return for help winning public contracts. Prosecutors said the money was spent refurbishing a beach resort apartment for him.

In recent months, Lula has toured Brazil as if he were already campaigning, rallying crowds of supporters in rural areas that benefited from his poverty relief programs.

But in an interview in August he told Reuters that the conviction might mean his party will have to field a candidate other than him in the Oct. 7 election.