His position as secretary-general – taking care of administration, including branch membership and audits for conferences – makes him one of the most important candidates for any group to have on its side.
Mantashe, like Deputy President Cyril Ramaphosa, comes from a trade unionist background and some in Cosatu are likely to back his candidacy.
As a former chairperson of the SACP, additional support for Mantashe is also likely to come from the communist bloc in the ANC.
An endorsement from the Eastern Cape – Mantashe’s home province – is also likely to boost his chances. He has been associated with Gauteng because the province has become his primary residence and he is a branch member in the Ekurhuleni region.