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Mpumalanga will be in the spotlight this weekend when provincial chairman and premier David Mabuza battles it out for the province's top position against health MEC Clifford Mkansi.
The election is expected to be hotly contested given Mkansi's track-record.
He is a former secretary of the award-winning Sondelani branch at Thulamahashe outside Bushbuckridge.
Mabuza, on the other hand, has received overwhelming support during the ANC regional conferences.
"It must be borne in mind that the province's four regions have all put their weight behind Mabuza during regional conferences.
"But his re-election as provincial chairman could be difficult because Cosatu, the ANC Youth League and the SACP have already voiced their disapproval of him as leader," said a provincial executive committee member who spoke on condition of anonymity.
A win by Mabuza - a known Zuma ally - will be an indication of how the province will vote in Mangaung.
The conference will be held at Nelspruit's Mbombela Stadium between Thursday and Sunday.
The other three provinces that are yet to go to their elective conferences include Free State, KwaZulu-Natal and Eastern Cape.
This has to happen before the end of May following an instruction from the ANC national executive committee that all provinces must have had their conferences before the party's policy conference in June.
ANC spokesman Keith Khoza said: "Part of the directive was that all provinces must have completed their audits before June except for Limpopo and North West, which had their conferences last year."
Free State province's branches go to branch general meetings (BGM) this week.
"The party caucus this weekend decided to officially open nominations today where premier Ace Magashule's contender, if any, is poised to emerge," said ANC provincial spokesman William Bulwane.
Free State will hold its elective between May 25 and 27.
Independent political analyst Elvis Masoga yesterday said current developments favoured President Jacob Zuma to retain his position as party leader.
"It is a known fact that the four provinces have leaders who are known Zuma supporters. "It is only Limpopo and Northern Cape which are known to be 100% against Zuma.
"North West and Gauteng are divided while Western Cape was unpredictable.
"Remember, Zuma was recently booed by members of the youth league during his visit to the province," added Masoga yesterday.