Parliament is due to decide on Tuesday whether to greenlight proceedings to remove him from office, after a report by an independent panel found that he "may" be guilty of serious violations and misconduct.
A simple majority in the National Assembly, where the ANC has 230 of the 400 seats, would be sufficient on Tuesday to initiate the impeachment process.
An impeachment vote itself would need the support of a two-thirds majority of MPs to succeed.
He was rumored to be on the verge of resigning earlier this month. But in a show of confidence, he campaigned on the streets of Cape Town over the weekend.
"There's no issue. There's no crisis. Just relax," he told reporters as, greeted like a star by cheers and camera flashes, he shook hands with supporters and patted children's heads.
Last week, the 70-year-old president went on the counter-attack, asking the country's top court to annul the investigative report.
The ANC's national executive vowed last week to close ranks around Ramaphosa and vote down any attempt to force him from office.
That decision upset some within the party who said the executive had forced their hand.
Dissenting voices included former health minister Zweli Mkhize, 66, who is challenging Ramaphosa for the ANC leadership.
But party officials seem confident there will be insufficient votes in parliament to start impeachment proceedings.
The vote comes just three days before Ramaphosa's party, the African National Congress (ANC), meets for its five-yearly conference to elect a new leader.
The president is the front-runner of the two candidates for the top ANC post - which is also the key to him possibly staying on as head of state for a second term.
"(Lawmakers) normally tow the party line. The ANC is on top of it," a senior party official told AFP on condition of anonymity.
The vote might even not happen at all, analysts say.
That would ease pressure on Ramaphosa ahead of the ANC leadership election.
"There is a possibility that the speaker of National Assembly, who is a political ally of Ramaphosa, decides to postpone the whole process and says, 'Let's have it next year'," said political scientist William Gumede.
The president, who was a wealthy businessman before entering politics, found himself in hot water in June when South Africa's former spy boss filed a complaint against him to the police.
Arthur Fraser alleged Ramaphosa had concealed the theft of several million dollars from his game and rare cattle farm in 2020.
He accused the president of having the burglars kidnapped and bribed into silence.
A police inquiry is ongoing but Ramaphosa has not so far been charged with any crime and has denied wrongdoing.
He has acknowledged the theft of $580,000, which was stashed under sofa cushions at his farm, but said the money was payment for buffalo bought by a Sudanese businessman.
