Mr Chamisa says he is only awaiting for the Zimbabwe Electoral Commission to officially announce the election results.
He and 75-year-old President Emmerson Mnangagwa were the main contenders in Monday’s election, which was the first since long-ruling Robert Mugabe was removed in a bloodless coup last November.
If the Zimbabwe Electoral Commission confirms Mr Chamisa’s claims, Mugabe’s former party, ZANU–PF, will be out of office for the first time since Zimbabwe became independent in 1980.
At the age of 40, Nelson Chamisa is Zimbabwe’s youngest ever presidential candidate.
He was born in Masvingo on February 2, 1978.
Mr Chamisa holds a bachelor’s degree in political science and public administration, and an LLB (Honours) from the University of Zimbabwe.
He is a qualified lawyer and a church pastor who has worked for Harare law firm Atherstone and Cook since November 2014.
As head of the Zimbabwe National Students Union in the late 90s, Chamisa organised various demonstrations against Robert Mugabe’s government.
In 1999, he joined as a student the opposition Movement for Democratic Change (MDC).
Throughout his life, he experienced first hand the risks of opposing the ruling party, having been jailed several times for his political activities.
In March 2007 he was attacked at Harare International Airport as he attempted to leave the country for Belgium.
He was admitted to a hospital with a broken skull.
On the current situation in Zimbabwe, he said, “There is no security.
“There is no protection.
“All of us are at risk.”
He was hospitalised for five days and the attack was widely blamed on Mugabe’s ruling party ZANU-PF.
He became party leader this year after the death of veteran Morgan Tsvangirai.
In an interview with AFP, he claimed his youth will be the force that propels him to election victory.
He said: “People are connecting with young leadership.
“Young people are taking charge, look at France, look at Canada… look at the United States.”