Zimbabwe’s first general election since Robert Mugabe was ousted in a military coup has been called for 30 July.
That was an interim measure and elections will now appoint the president and the members of both houses of parliament.
Mr Mugabe will not be on the ballot and, for the first time in 20 years, nor will former opposition leader Morgan Tsvangirai, who died of cancer in February at the age of 65.
While many were optimistic after Mr Mugabe stood down, some have become disenchanted that the country’s authoritarian system continues despite the change of leader.
The current president has pledged the vote will be free and fair.
He wants to rejoin the Commonwealth and is keen to attract foreign investors to return to Zimbabwe, two decades after many pulled out.
Mr Mnangagwa, 75, has invited Commonwealth officials to monitor voting in Zimbabwe for the first time since 2002.
His main challenger is 40-year-old Nelson Chamisa, from Mr Tsvangirai’s old party – the Movement for Democratic Change (MDC).
He has been drawing large crowds at rallies but analysts say Mr Mnangagwa could benefit from his position and the resources it offers.
Eldred Masunungure, a professor of political science at the University of Zimbabwe, said: “Though the election looks like it will go to the wire, the greater likelihood, based on cold-blooded analysis, is that experience, depth and state incumbency will triumph over youthfulness.”
Some 60% of Zimbabwe’s 5.4 million voters are under 50, according to official data.
Zimbabweans living outside of the country have been prevented from voting by a court.
Potential candidates have until 14 June to register. If no candidate gets more than 50% in the 30 July vote, a run-off will take place on 8 September.
Mr Mnangagwa is said to have the backing of the army.
Critics say the incumbent president, nicknamed Crocodile, was a loyal follower of Mr Mugabe and responsible for a crackdown on rebels in the mid-1980s that human rights groups say resulted in the deaths of 20,000 civilians.
In March, supporters of Mr Chamisa were blamed for attacks on the supporters of another opposition leader, Thokozani Khupe, a vice-president of the MDC and former deputy prime minister when Mr Tsvangirai was in government.