Brasília, Brazil(CNN) President Dilma Rousseff insisted Monday she had committed no crime and said she was proud that she'd been "faithful to my commitment to the nation."
Brazil's post-Olympic high came to an end as Rousseff's impeachment trial began. Her remarks from the Senate floor suggested the suspended president had no intention of accepting the bid for her impeachment without a fight.
"I'll plan and fight for democracy," she said. "I don't fight for my term for the power, but I fight for the democracy for truth and justice and the people of my country."
It's not clear if an impassioned speech will do any good. The tide of opinion is against her, and the appearance is widely expected to be her last public address.
It's a jarring return to reality for the South American nation, with the final vote in the drama following the celebrations that came with Rio de Janeiro hosting the 2016 Summer Olympics.
The impeachment process has dragged on for months, predating the Olympic torch lighting ceremony -- a glitzy showpiece that, despite orchestrating, Rousseff was barred from attending. It's a political crisis that ordinary Brazilians could do well without -- the country is trying to pick itself out of recession.
'It's not an impeachment'
Rousseff calls the impeachment an attempt at a power grab by her rivals, saying her government has long been the target of political sabotage.
"When Brazil or when a president is impeached for a crime that they have not committed, the name we have for this in democracy, it's not an impeachment, it is a coup," she said in May after the Senate voted to launch the proceedings.
The heir-apparent to former President Luiz Inacio Lula da Silva, Rousseff was re-elected by a narrow margin in 2014, but soon a recession and a cross-party corruption scandal put an end to any political goodwill she might have earned.
She has been suspended from all official duties and has -- for the time being, at least -- been replaced by her former deputy, Michel Temer, a man she accuses of stabbing her in the back.
The final vote to impeach, which needs to be ratified by a two-thirds majority of 81 senators (54 votes), is expected Tuesday.
If the vote passes -- and most observers expect it to do so easily -- Temer will become the country's new president until 2018's general election, at least. He would inherit a tattered economy along with the keys to the presidential palace in Brasilia.
What do the polls say about Rousseff?
Rousseff's popularity soared when she was elected Brazil's first female President in 2010.
Lately, her approval rating has been hovering around 10%, according to recent polls.
For some context, pollster Ipsos said in a report in April that Rousseff's approval rating was around 15%, while former US President Richard Nixon's approval rating was 25% before he resigned and former US President Bill Clinton's approval rating was 65% before his impeachment.
Rousseff told CNN earlier this year that low approval ratings shouldn't fuel a push to remove a democratically elected leader from office.
Brazilians protest -- for and against -- president's impeachment
Interim president Michel Temer said Brazil must be united to move forward. "We don't have a lot of time. We have to be committed so we can implement the reforms that the country needs," he said.
Five things to know about Temer
The decision to impeach Rousseff came after about 20 hours of debate in the Senate. She's been suspended for 180 days, and while she'll retain the title of President, she won't perform any of the duties of the office.
Rousseff: What she keeps, what she loses
Riot police arrest a Rousseff supporter during a protest in Sao Paulo, Brazil on May 12.
Fifty-five of 81 members of Brazil's upper house voted in favor of the motion to impeach Rousseff on Thursday. Twenty-two voted against.
Along with the precarious state of the Brazilian economy, the country faces a number of other, high-profile challenges, from dealing with the Zika virus to a fraught 2016 Olympics, which are due to open in Rio de Janeiro in August.
What is she accused of?
She faces accusations that she doctored accounts ahead of her re-election in 2014 to hide a budget shortfall and to keep funding popular social programs. Rousseff maintains she didn't do anything illegal and is expected to counter that some of the lawmakers investigating her are under investigation for corruption.
"I have made mistakes, but I have not committed any crimes. I am being judged unjustly, because I have followed the law to the letter," Rousseff has said.
Her government has been fighting corruption allegations for a while.
A sweeping investigation into a multimillion-dollar kickback scheme at the state-run oil company Petrobras embroiled dozens of the country's leading businessmen and politicians. While she isn't accused directly of profiting, Rousseff was the chairwoman of the state oil company during many of the years of the alleged corruption.
World leaders who left office
Brazil's Dilma Rousseff was ousted from the presidency on August 31, 2016, when the
Senate voted 61-20 to find her guilty of breaking budgetary laws in an impeachment trial. Rousseff had been suspended earlier. Here are other world leaders who left office before the end of their term, either by choice or by constitutional action:
Richard Nixon: In 1974, five years after he was first elected, Nixon became the first U.S. President to resign from office. He stepped down after the
Watergate scandal, which stemmed from a break-in at the Democratic National Committee office during the 1972 presidential campaign.
Margaret Thatcher: The United Kingdom's first female Prime Minister,
who was called the "Iron Lady" for her personal and political toughness, served from 1975 to 1990. She was forced to resign in 1990 during an internal leadership struggle.
Shinzo Abe: After serving just a year as Japan's Prime Minister, Abe resigned from his post in 2007 after low approval ratings and scandals amongst several government ministers.
He was re-elected in 2012.
Tony Abbott: One of Australia's most controversial leaders in recent history, Abbott
was toppled in a leadership challenge just two years into his role. After his final speech, Abbott ended his term with a tweet: "Thank you for the privilege of being Prime Minister. My love for this country is as strong as ever."
Pervez Musharraf: He rose to power in a bloodless coup in 1999, but the former Pakistani President
left office nine years later after an erosion in power coupled with economic problems and accusations that included corruption. Musharraf denied doing anything for personal gain.
Silvio Berlusconi: Berlusconi weathered many crises, including sex scandals and corruption trials, during his three terms as Italy's Prime Minister. But
the loss of his parliamentary majority -- and with it his ability to command the government -- was a blow from which Berlusconi could not recover in 2011.
Thabo Mbeki: Mbeki rose to power in 1999 after Nelson Mandela -- South Africa's first black President -- retired. Mbeki had been Mandela's deputy. He
resigned in 2008 after his party asked him to. The request came after a judge threw out the corruption, fraud and racketeering charges against Mbeki's political rival, Jacob Zuma, calling them invalid and accusing Mbeki's government of political interference in the case.
Tony Blair: The former British Prime Minister was in office from 1997 to 2007.
He resigned with his reputation clouded by the disastrous outcome of the Iraq war and the "Cash for Honors" scandal, allegations that his ruling Labour Party promised honors -- including seats in the upper House of Lords and knighthoods -- in return for loans to help a 2005 general election campaign. (No charges were brought in the case.) He handed the Prime Minister post to Gordon Brown, who himself would resign a few years later.
Boris Yeltsin: The Russian President
announced his resignation on New Year's Eve in 1999, putting then-Prime Minister Vladimir Putin in charge. During the announcement, Yeltsin apologized for failing to live up to early expectations as the architect of Russia's new democracy.
Fernando Collor de Mello: Collor had served for just two years as Brazil's President when he resigned in 1992, weeks after impeachment proceedings against him had begun. Allegations of corruption had started just 100 days into his presidency. Collor was convicted by the Senate and barred from holding office for eight years. Now he is a senator himself.
How much of her term is left?
Rousseff's term is set to end in December 2018. Right now, she's suspended for up to 180 days, and Temer is the acting president. If she's found guilty in the impeachment proceedings, she'll be removed from office. She insists she'll stick around to see out her term, but Tuesday's vote will determine that.
Who is behind the impeachment?
Again, like many things in Brazil's tumultuous political landscape, it depends on whom you ask. But in the country's lower house, one man had been leading the charge: Eduardo Cunha.
Cunha launched a bid to impeach Rousseff in December. He was the speaker of the lower house until April when the Supreme Court suspended him from all congressional duties over allegations of obstructing corruption investigations and intimidating lawmakers. He resigned in July.
CNN's Catherine E. Shoichet contributed to this report.