With more than 20 per cent of votes counted in South Africa's landmark general election, the ruling ANC appears set to win a fifth consecutive term in office, but with a significantly reduced margin.
After millions of determined South Africans - including hundreds of thousands of first-time "born free" voters - turned out in force, the African National Congress (ANC) was ahead with more than two million ballots counted by 1330 AEST on Thursday.
The African National Congress held 56 per cent of the vote, down significantly from the 66 per cent it won at the last election, amid successive scandals surrounding its leader, President Jacob Zuma.
The opposition Democratic Alliance was seen nearly doubling its share of the popular vote to 30 per cent, although the tallies could still change significantly.
Twenty years after South Africans of all colours wowed the world by voting to end apartheid, they had shrugged off sporadic violence to cast their ballots on Wednesday in the first poll since the death of democratic hero Nelson Mandela.
His African National Congress was widely expected to win, but strong turnout in South Africa's cities could prove a boon for the party's political foes.
Pansy Tlakula, chairperson of the Election Commission, said voting "proceeded without serious incident in almost all areas.
"Very high volume of voters were reported in metro areas throughout the country."
Anything less than 60 per cent for the ANC would be seen as a major upset and raise questions about Zuma's leadership.
Casting his ballot in his home village of Nkandla, Zuma said he expected the "results will be very good", but conceded the campaign had been "very challenging".
Zuma has been a lightning rod for criticism of the ANC and has been pilloried for the government spending $US23 million ($A24.89 million) of taxpayers' money to upgrade his private home.
Commentators have billed this election as the last to be dominated by the memory of apartheid.
A new generation of South Africans - numbering around two million, with around 646,000 registered to vote - were born after the end of apartheid and cast their ballots for the first time.
A record 25 million voters registered for the elections despite mounting anger over joblessness, inequality and corruption.
"People died for this right. They must not waste it," said Nobel peace laureate Desmond Tutu, a liberation struggle veteran who has said openly he will not vote for the ANC this time.
The eve of the ballot was marred by isolated incidents of violence, with police and 1850 troops deployed to several areas to keep order.
