Zuma, who survived a rape trial and his dismissal as the country’s deputy president by Mbeki over corruption allegations, took 60% of the nearly 4,000 votes at the party’s national conference in a dramatic political comeback. His victory potentially opens the way for him to become South Africa’s next president at the 2009 general election, if he is not blocked by a longstanding graft investigation. The vote amounted to a repudiation of Mbeki, a man who has dedicated his life to the ANC but who was seen as increasingly authoritarian, power hungry and out of touch with ordinary South Africans.

Zuma’s supporters at the conference celebrated the news of his victory by singing and dancing and waving signs, saying that if Mbeki stayed, it would be like Zimbabwe. Zuma’s allies also won other important party leadership posts, forcing out the Mbeki camp.

Jim Mkandawire, a delegate who voted for Zuma, said before the result that it was time for a change. “We have done it, as we have been saying all along. Zuma is an unstoppable tsunami,” he said. “I love Mbeki but believe that politics in the ANC is like a relay. He has to hand over the stick to another person.”

Mbeki made a gesture of reconciliation in what has been a bitter and at times a dirty campaign, by accompanying Zuma on to the platform after his victory was announced. Mbeki was defeated by Zuma’s organisation among the poor, who believe they have been neglected while the ANC elite became rich, and by those disturbed at his efforts to retain control of the party, even after he ceases to be the president in two years.

But Zuma’s victory may prove to be the beginning of a fresh power struggle with Mbeki, as the two men battle for dominance for the remainder of the president’s term, until the general election.

Mbeki is likely to influence whether the director of public prosecutions charges Zuma for allegedly accepting substantial bribes from a French weapons company.

Zuma’s financial advisor has already been jailed for funnelling him the payments.

Zuma’s camp has accused Mbeki of pursuing the graft investigation as a political vendetta and has warned that it might use the ANC’s domination of parliament to force an early general election if charges are brought.