BRASÍLIA — Brazil’s Senate will vote today on whether to send suspended president Dilma Rousseff to within a final step of losing office, bringing the Olympic host country’s political crisis to a climax.

Rousseff’s opponents only need a simple majority of the 81 senators’ votes to open an impeachment trial. They look set to clear the threshold easily, although the debate is expected to be a marathon session stretching into the early hours of Wednesday.

It is the final vote before the one that will decide Rousseff’s ultimate political fate, when a two-thirds majority would be needed to strip her of her power and end 13 years of leftist rule in Brazil. That vote is expected to take place around the end of August, just days after the Rio Olympics end.

The Senate suspended Rousseff, Brazil’s first woman president, on May 12 over accusations of illegal accounting practices and fiddling the budget to mask the slump in the economy. She condemns the process as a coup.

The timing could hardly be more awkward for Brazil, which was meant to be showcasing its burgeoning economic clout and political stability with South

America’s first Olympic Games in full swing.

Instead, unpopular interim president Michel Temer -- formerly the vice president -- is struggling to drag the country out of its worst recession in decades as the Senate debates what to do with his former boss and bitter enemy.

Rousseff is accused of spending money without congressional approval and taking out unauthorized loans from state banks to make the national budget look better than it really was as she campaigned for re-election in 2014.

She says such maneuvers were common practice under previous administrations and do not amount to an impeachable offense.

Her allies from the Workers’ Party point out that many of the lawmakers accusing her are implicated in corruption cases arguably far more serious than accounting tricks.

But her enemies say her fate is already sealed.

"The president is ever more isolated, a very pronounced isolation that has only gotten worse in recent weeks and now even includes her own party," said Senator Aloysio Nunes of the opposition party PSDB.

"I have no doubt that the vote will be in favor of impeachment, as it will be at the final trial," he said.

Messy end game

The impeachment trial is set to open around August 25 -- four days after the Olympics closing ceremony -- and last five days before the judgment vote.

The political mess makes an unfortunate backdrop to the Olympics, awarded to Rio de Janeiro in 2009 when Rousseff’s predecessor and political mentor Luiz Inacio Lula da Silva was hugely popular.

Now, not only is Rousseff facing oblivion, but Lula is set to go on trial for obstruction of justice charges. He also faces corruption allegations that could sink his hopes of returning to power in the 2018 elections.

Rousseff, 68, is a former leftist guerrilla who was jailed and tortured by the country’s military regime in the 1970s.

She rode Lula’s coattails to power when term limits forced him to step down in 2011.

But the buoyant national mood soon deflated as Brazil’s booming economy sank into its worst recession in 80 years and a huge corruption scandal erupted at state oil giant Petrobras.

Rousseff is not facing corruption charges in the wide-ranging scandal. But she has been tainted by its stain on her Workers’ Party, which is accused of lining its coffers with some of the missing billions.

If Rousseff is removed from office, Temer, her center-right running mate turned opponent, will become the full-fledged president until the next presidential election in 2018.

He has urged the Senate to move quickly, saying "people need to know who the president is."

Disgust with the entire political class is widespread in Brazil.

Temer, 75, presided over the Olympics opening ceremony Friday, drawing boos from the crowd -- just as Rousseff did at the opener of the 2014 World Cup. — AFP