Mujuru is faced with the challenge of keeping all these more or less autonomous and unpredictable groups on side until December 2014 in the face of inevitable attempts from Mnangagwa's group to pressure or persuade those less committed loyalists to defect.
Secondly, confidence in Mujuru's position assumes Mnangagwa's group has thrown in the towel and accepted that it will play second fiddle in ZANU-PF politics. This seems highly unlikely. The rivalry between Mujuru and Mnangagwa has been simmering for a long time and the justice minister has proven in the past that he is not beyond using subversive means to get what he wants.
Finally, any assurance in Mujuru's rise accepts at face value the suggestion that the presidential succession will in fact be predicated on electoral success within the party. In reality, however, gaining the endorsement of the securocrats and the blessing of Mugabe could be just as important as any election.
Friends in powerful places
Looked at from this perspective, the fact that Mnangagwa's faction does not seem overly rattled by the results in the provincial elections makes more sense.
Zimbabwe's military have long played a pivotal part in ZANU-PF politics, and many believe Mugabe would not have had the same staying power without the security elite's endorsement. These securocrats might not have a vote, but it seems that they do have a preferred candidate.
Over the years, Mnangagwa has cultivated a much stronger relationship with the intelligence community and military than Mujuru, partly through his previous role of defence minister. Furthermore, the belief that Mnangagwa would be more likely to seek continuity as president rather than change also plays well to the securocrats looking to maintain their privileged positions of power.
Gaining Mugabe's endorsement will also be crucial. After all, the long-time president still dominates the party, and through ZANU-PF history Mugabe's hand has been central in ensuring the rise or fall of various politicians.
Looking to his successor, Mugabe's will presumably want a leader that can keep the party together, but crucially also one who will allow him to continue playing a part in politics from behind the scenes. The person who seems to fit this bill closest is the figure who has long been considered Mugabe's blue-eyed boy, Mnangagwa, and there have been signs that he is indeed Mugabe's preferred candidate.
For example, when Mugabe held a press conference on the eve of the July 2013 election, he was flanked by the press secretary on one side and Mnangagwa on the other. Asked if Mnangagwa's presence meant he was next in line to the throne, Mugabe seemed to be caught off guard and hastily claimed the then defence minister had just dropped by for a visit. In more concrete terms, however, it is notable that Mugabe has always assigned important government ministries to Mnangagwa - including state security, home affairs, defence and justice - and that Mnangagwa is believed to be one of just a few ZANU-PF officials allowed to maintain direct and close ties to Zimbabwe's security community, a privilege not understood to be granted to Mujuru.
It is possible Mugabe considers Mujuru more of a lightweight than the hard-line Mnangagwa and may believe she will struggle to deal with the opposition, foreign interests, and the party's internal tensions. He may also be concerned that ZANU-PF's image of being a fearless revolutionary party will be lost under Mujuru.
In fact, Mugabe's ties to Mujuru have always been somewhat opportunistic, with the president arguably maintaining close links with her to appease Solomon Mujuru, Joice's powerful late husband.