As Nelson Mandela was being laid to rest, an opinion poll showed his political heir Jacob Zuma losing support over claims of abuse of public funds.
A survey for the Sunday Times newspaper showed 51 per cent of registered voters of the ruling African National Congress (ANC) want the president to resign.
The results of the survey conducted by the Ipsos market research company comes in the same week that Zuma was booed at Mandela's memorial service in Soweto.
Of the 1,000 ANC voters polled in a representative survey, 33 per cent said they were less likely to vote for the ANC over allegations that Zuma used about US$20 million of public money to upgrade his private residence.
And 42 per cent of the voters said they believed he had abused taxpayer funds.
On Tuesday, South Africans booed their president at the memorial service for Mandela, whose legacy is one of selflessness and sacrifice.
The ANC had claimed the booing was orchestrated by other political parties.
But many of those who jeered later spoke of their disillusionment and anger at Zuma's lifestyle at a time that many South Africans remain poor, unemployed and without formal housing in a society that is among the world's most unequal. Zuma's immediate predecessor Thabo Mbeki, though unpopular at the time of his ousting from the party by Zuma in 2008, received a warm welcome at the memorial.
Mbeki, who succeeded Mandela as president in 1999, challenged South Africa's leadership to ask if they were living up to Mandela's standards, in a pointed public challenge to his ANC comrades.
"I think to celebrate his life properly we need to ask ourselves a question about the quality of leadership," Mbeki told a prayer gathering in Johannesburg.
The ANC under Zuma has come under fire over claims of nepotism and corruption.
The party is preparing for national elections next year.
Despite growing disgruntlement, the party retains a firm grip on power on the back of its historic status as the liberator of a long-oppressed people, and will likely retain a large majority.