Cape Town - The country's national election on Wednesday is set to test whether the ruling ANC party has staunched a decline in popularity caused by corruption scandals, lacklustre growth and record unemployment.
The party is still expected to win the vote, but the result will reveal whether its new leader, President Cyril Ramaphosa, can reverse growing resentment among South African voters.
The election comes 25 years since Nelson Mandela led the African National Congress (ANC) to power in the country's first multi-racial ballot, which marked the globally-celebrated end of apartheid rule.
Support for the ANC has fallen in every election since 2004 with the party winning just 54 percent in 2016 local elections, compared with 62 percent in the last national vote in 2014.
Ramaphosa, 66, took office last year when Jacob Zuma was forced to resign as president by the ANC after a nine-year reign dominated by corruption allegations and economic woes.
Most opinion surveys suggest the ANC will secure nearly 60 percent of the vote on Wednesday, though one poll suggested its share could slide below 50 percent.
Ramaphosa, seen as a pro-business moderate, is a former anti-apartheid activist and trade union leader who was Mandela's apparent favourite to succeed him as president.
After being outmanoeuvered in that race, Ramaphosa instead became a wealthy entrepreneur before serving as Zuma's vice president.
ANC look to win big
"Ramaphosa gives hope to the electorate that things can go better," Susan Booysen, a political analyst at the University of the Witwatersrand in Johannesburg, told AFP.
"If the ANC had gone into an election under Zuma, it would not have won with an outright majority."
The London-based Eurasia risk consultancy said that an ANC victory with 55 percent or less of the vote would damage Ramaphosa and strengthen aggrieved supporters of Zuma within the party.
"This will be the first time that Ramaphosa's popularity will be measured by voters," it said in a briefing paper.
"He is not aligned with Zuma and is driving an anti-corruption campaign and reform agenda aimed at reversing the damage inflicted during Zuma's tenure."
The ANC has been confronted by deepening public anger over its failure to tackle poverty and inequality in post-apartheid South Africa.
The economy grew just 0.8 percent in 2018 and unemployment hit a record high of nearly 28 percent in 2017.
State-owned companies were at the centre of corruption scandals under Zuma, with power-supplier Eskom now laden with huge debts and forced to ration electricity to many homes, shop and offices.
Wednesday's election will have 48 parties on a ballot paper, though only the main opposition centrist Democratic Alliance (DA) and the radical-left Economic Freedom Fighters (EFF) are also major political players.
The DA hopes to shed its image as a white, middle-class party as its first black leader, Mmusi Maimane, fights in his first general election since he took the helm in 2015.
According to Intellidex Capital research, the party is forecast to make only marginal gains from the 22 percent it won in 2014 after struggling to make ground against Ramaphosa -- a more widely popular figure than Zuma.
Leftist radicals on the up?
But the radical leftist EFF, founded just six years ago by a former ANC youth leader Julius Malema, is predicted to make major inroads, growing from 6.3 percent to a forecast 11 percent.
The party, which appeals mainly to young voters and the poor, has centred its election campaign on its flagship policy of seizing land from largely white owners to give to poor blacks.
Enforced land redistribution has also been adopted as a policy by Ramaphosa's government -- alarming some investors.
Wednesday's provincial elections will also measure ANC fortunes, with the party in a close fight with the DA for control of Gauteng, which includes the capital Pretoria and the economic hub Johannesburg.
Ahead of the vote, tens of thousands of supporters attended rallies at the weekend hosted by the major three parties.
"We are humble enough to admit our mistakes," Ramaphosa told the ANC gathering.
"We have taken decisive steps to fight corruption... The era of immunity is over, we are now entering a period of accountability."
Some 26.8 million voters are registered to cast ballots at 22 925 polling stations.
Early results will emerge on Thursday with an official winner declared on Saturday.
The party that wins most seats in parliament selects the president, who will be sworn in on May 25.