South Africa’s ruling African National Congress is about to elect a new leader, but it enters its national conference this weekend deeply divided over who the party’s next president should be.

The litany of legal challenges currently facing the party illustrates the scale of those divisions. Last Monday, the outcomes of five of its nine provincial-level elective conferences were still being challenged through the courts.

Similar disputes unfolded at the ANC’s earlier regional and branch-level elections in October and November. In each case, different ANC factions were in part fighting to control their structures so they could appoint voting delegates to attend the party’s 54th national conference, which begins on Saturday.

By late on Friday, outgoing ANC president Jacob Zuma’s preferred candidate to succeed him, Nkosazana Dlamini-Zuma, had suffered a number of setbacks ahead of the poll.

More than 100 voting delegates from three provinces who were expected to back her candidacy were barred from attending the vote by South Africa’s courts.

The delegates, who were banned for issues such as irregularities with their branch election processes, come from KwaZulu-Natal, the Free State and the North West.

Although there are seven presidential candidates vying to succeed Zuma, the race is really between the two frontrunners: ANC deputy president Cyril Ramaphosa and Dlamini-Zuma, a senior party member.

For most observers, this is the tightest ANC election since 1994, and literally too close to call.

Five-day conference

As a result, supporters of both candidates are doing everything in their power to win over each of the more than 5,000 voting delegates who will attend the five-day conference at the Nasrec Expo Centre in Soweto, Gauteng Province.

More than 2,500 nominations will be needed to win, and the successful candidate’s margin of victory may only be a double-digit figure, according to predictions based on partial ANC branch nomination tallies.

African National Congress presidential candidate Nkosazana Dlamini-Zuma (centre): critics claim an ANC under her leadership would mean a continuation of corruption. Photograph: Wikus De Wet/AFP/Getty

More than 90 per cent of the voting delegates come from the party’s branch structures, with the remainder coming from the youth, women and veterans’ leagues, as well as the provincial and national leadership structures.

The delegates will also elect the ANC’s other top-five positions and new members to the national executive committee, the party’s top decision-making body.

The two frontrunners represent very different futures for the ANC in terms both of policies and the direction they want to take the movement.

Ramaphosa, who is also South Africa’s deputy president, is a lawyer and former trade unionist who became a billionaire businessman in the post-apartheid era before returning to active politics in 2012.

Backed by the anti-Zuma faction in the ANC, he has promised to tackle the endemic corruption that has undermined the party under Zuma. He has advocated stabilising the economy through “inclusive growth” and the implementation of pro-business policies.

His election to the ANC’s top job would be bad news for Zuma, whose term as South Africa’s president only ends in 2019. If Ramaphosa wins, Zuma will likely be recalled early because of his poor standing with the voting public. Such an eventuality would leave Zuma exposed to criminal prosecution on a range of pending corruption charges.

Technocrat and traditionalist

Dlamini-Zuma, the president’s ex-wife, has led different government ministries since the ANC came to power in 1994. She is seen as a competent technocrat and a traditionalist by nature. Most recently she was chairwoman of the African Union Commission.

Dlamini-Zuma is backed by a faction in the ANC that remains loyal to her ex-husband, an association which has tarnished her image, although she maintains she is independent.

In terms of policies, Dlamini-Zuma has espoused a radical approach to transforming South Africa’s faltering economy, such as nationalising the Reserve Bank. Her supporters also advocate for expropriating land without compensation.

During her campaign she promised to empower poor blacks and loosen the stranglehold that large white-owned companies have on different industries.

She has also talked little about fighting corruption during her election campaign. Consequently, Zuma is expected to be safer from prosecution if she becomes the ANC’s new leader, and he may well be allowed to see out his term as South Africa’s president.

As a result, Dlamini-Zuma’s critics claim that an ANC under her leadership means a continuation of the corruption that is destroying the ruling party.

Business links

Those who stand against Ramaphosa believe he is too close to big business and does not have poor black South Africans’ interests at heart.

At the start of December, Ramaphosa looked to have an early lead in the presidential race when it was revealed he had secured the majority of the party’s submitted branch nominations.

He was nominated for the position by 1,862 ANC branches compared with the 1,309 that backed Dlamini-Zuma, according to tallies released by the ruling party’s provincial structures. But a large number of branches did not submit their nominations on time.

A major concern ahead of the conference is the possibility that vote-buying will take place. Although delegates are supposed to vote in line with their branch’s leadership preferences, they cast their ballots in secret, which leaves individuals open to potential bribery.

Supporters of both camps have already accused each other of trying to bribe delegates to vote for their candidates, which is increasing the already high tensions.