BRASILIA (Reuters) - With a spreadsheet listing undecided lawmakers, Brazilian President Michel Temer is working the phones to nail down support to block a corruption charge in a crucial congressional vote next week that will decide his political future, close aides said.

Brazil's President Michel Temer arrives to a ceremony at the Planalto Palace in Brasilia, Brazil July 27, 2017. REUTERS/Adriano Machado

The lower house will decide on Wednesday whether Temer should be put on trial by the Supreme Court for allegedly taking bribes from the world’s largest meatpacker, JBS SA.

Even though Temer is widely expected to survive the vote, the country’s top prosecutor has said he will file at least two more graft-related charges against Temer in coming weeks.

Wednesday’s vote will be a gauge of how much support the unpopular president has to press ahead with reform of the costly pension system that is needed to overcome Brazil’s fiscal crisis and help Latin America’s largest economy out of deep recession.

Temer is taking no chances.

The Contas Abertas watchdog group, citing Finance Ministry data, says he has freed up funding for lawmakers’ districts at an unprecedented rate to secure their support to bury the corruption charges, with outlays soaring to 4.2 billion reais ($1.33 billion) since June, compared to just 100 million reais in the first five months of this year.

Some members of his governing coalition, including his closest ally the Brazilian Social Democracy Party (PSDB) are split over whether it is time to abandon the corruption-plagued president even if they fully back his economic policies.

“Last week we had 261 lawmakers for Temer and 171 against him,” said Beto Mansur, the government’s deputy whip in the lower chamber, who said he handed the president a computer spreadsheet with the names of the 80 undecided politicians. “He managed by phone to convince 20 to vote for him.”

“We have to win with a large margin to show Brazilian society that the charges are not a threat to Temer, so we can put this behind us and get on with the pension reforms and other economic measures Brazil needs,” Mansur told Reuters.

Under Brazil’s constitution, two-thirds of the lower house deputies (342 of 513) must vote in favor of the charge for it to proceed to the Supreme Court, which in turn must rule on whether to go ahead with a trial. Temer would be suspended for 180 days pending the outcome of a trial.

The corruption scandal has undermined the scant popularity Temer had, making it harder for lawmakers to support him ahead of next year’s elections. A poll published on Thursday showed his government’s approval rating fell to just 5 percent, and 87 percent of those surveyed say they do not trust him.

In Temer’s presidential offices, staffers are worried but confident the government has the votes to prevail.

“We have 280 votes for sure, and could pass 300. Any absences among lawmakers will help the president,” Marco de Freitas, Temer’s chief spokesman, said in an interview.

“The charge lacks enough proof to put a president on trial. And the other charges are even less solid,” he said.

Several lawmakers, however, have told Reuters the next votes on two additional charges Prosecutor General Rodrigo Janot plans to file, including racketeering and obstruction of justice, will be a closer call for Temer due to the media spotlight shining on them and the proximity of an approaching election year.

Temer will meet with dozens of lawmakers on Monday and Tuesday when Congress returns from recess to press his case on the eve of the vote, de Freitas said.

Political analyst Thiago de Aragão expects a cabinet reshuffle after the vote to reward coalition parties that most solidly backed Temer and consolidate the president’s realigned political base to move forward with his reform agenda.

“The question is will the Temer government have the power it had in May, before the JBS scandal, to pass pension reform, or will it have to water down the bill with more concessions,” said Aragão, partner at Brasilia consultancy ARKO Advice.