Zimbabwe's President Emmerson Mnangagwa and his main opponent, Nelson Chamisa, both say they are confident of victory in an election the previous day which observers deemed too early to call.
Subscribe now for unlimited access.
$0/
(min cost $0)
or signup to continue reading
Mnangagwa said he was receiving "extremely positive" information on the vote. Chamisa said earlier the opposition Movement for Democratic Change had done "exceedingly well" in the vote.
The 75-year-old Mnangagwa and Chamisa, 40, were the main contenders in Monday's election, the first since Robert Mugabe was removed in a bloodless coup in November.
Western diplomats and local observer groups said the race, which saw a turnout of 75 per cent, was too close to call.
The Zimbabwe Electoral Commission will announce official results within five days of the election although the outcome should be known well before then.
The winner faces the task of putting Zimbabwe back on track after 37 years under Mugabe which were tainted by corruption, mismanagement and diplomatic isolation that caused a crisis in a country that once had one of Africa's most promising economies.
"The information from our representatives on the ground is extremely positive!" Mnangagwa said on his official Twitter feed.
Chamisa had earlier said he was poised for victory, writing on Twitter: "Awaiting ZEC to perform their constitutional duty to officially announce the people's election results and we are ready to form the next government."
A Chamisa victory is unlikely to sit well with military generals who plotted Mugabe's ouster last November, and there could be a pushback.
Some of the generals who orchestrated the coup are now in government, including Vice President Constantino Chiwenga.
Many Zimbabweans worry that should Mnangagwa lose, some in the ruling party may not accept the result, given the huge risk they took in removing Mugabe.
Mnangagwa and ZANU-PF have said they will accept the result.
"If this guy loses there is no way they will hand over power," said Gift Machekera, pointing at a huge banner of Mnangagwa hanging on a building in Harare.
"Those who have the guns have the power. This is Africa."
Mnangagwa was viewed as the frontrunner, although the latest opinion polls showed a tight race. There will be a run-off on September 8 if no candidate wins more than half the votes.
A credible vote is essential if Zimbabwe is to exit painful sanctions and secure the donor funding and investment needed to stem chronic cash shortages.
Australian Associated Press