Harare - Ahead of Zimbabwe's crucial elections this year, the biggest opposition party has selected a charismatic lawyer and pastor to challenge the military-backed president in the first vote without former leader Robert Mugabe in decades.It will be a hard road for 40-year-old Nelson Chamisa, who became head of the MDC-T party this month after the February death from cancer of Morgan Tsvangirai.Chamisa will face President Emmerson Mnangagwa, a former confidant of Mugabe. Mnangagwa, 75, fell out with Mugabe last year amid factional squabbling and was sworn in after a military intervention in November.Chamisa is banking on sympathy for Tsvangirai, a prominent figure who challenged Mugabe and later joined a troubled coalition with him. Without Tsvangirai the MDC-T party has now fractured, with some violence."Tsvangirai has been our best foot forward. He had a lot of goodwill and I am inheriting all the positives. We are simply harvesting," Chamisa told The Associated Press in an interview held in a party boardroom adorned with pictures of his predecessor.Whatever happens at the polls expected in midyear, Zimbabwe will be experiencing something new.Generational issue Mugabe, 94, was the southern African nation's only leader since independence from white minority rule in 1980, a period that began with promise and descended into economic turmoil and repression as the aging ruler clung to power. In his first interview since his resignation, Mugabe last week called his ouster a "coup" and said "we must undo this disgrace".Like the ruling Zanu-PF party, the main opposition party is fielding a new candidate for the first time since it was formed.Zimbabwe's political landscape is still plagued by disunity. The electoral commission says there are over 100 parties in a country with 5.3 million registered voters.Mnangagwa, a veteran of the 1970s war against white minority rule and a long-serving Cabinet member, is under pressure to deliver fair elections in order to restore international ties after years of sanctions. He has said elections will be held "as scheduled", between July and August.Chamisa, 35 years younger than the president, called the "generational issue" central to the election. "I represent the new. Mnangagwa represents the past," he said in the AP interview.KEEP UPDATED on the latest news from around the continent by subscribing to our FREE newsletter, Hello Africa.FOLLOW News24 Africa on Twitter and Facebook. "Mnangagwa was important as a bridge. He helped us remove Mugabe so he is Zimbabwe's door out of the past, not to the future," Chamisa added.At his first rally as MDC-T president and presidential candidate early this month, Chamisa promised wide-ranging economic and democratic reforms and an upgrading of the once-prosperous country's technology.Thousands attended the rally in Chinhoyi, which is in Mugabe's home province. Supporters roared in disapproval when Chamisa announced he was shortening his speech because of a heavy downpour."We are not going anywhere," some shouted, forcing him to continue after refusing an aide's umbrella.A few supporters wore T-shirts with an image of Chamisa but most had old Tsvangirai shirts, a sign of the deceased politician's influence."Tsvangirai was our Moses. Chamisa is our Joshua," said 67-year-old Pertunia Chigarande. In biblical narratives, Joshua succeeded Moses and completed the deliverance of Israelites to the so-called promised land.Others have a less charitable view of Chamisa, a former student leader who was among the opposition party's top six officials at its formation in 1999. He has been accused of using violence against his own party rivals, an allegation that he denies.Solid social base "Chamisa has an unquenchable thirst for power. He is prepared to use violence to grab power, as he is doing now," said Thokozani Khupe, a party deputy who claims to be the rightful successor to Tsvangirai and whose supporters were involved in violent clashes with Chamisa loyalists this month.Internal party divisions could cost Chamisa "big time," said Harare-based political analyst Alexander Rusero. He said Mnangagwa's experience gives the youthful Chamisa "a major headache."Non-governmental organisations allege the ruling party is resorting to old tactics of intimidation by allowing its officials and traditional chiefs aligned to the party to force rural people to surrender voter registration details. The electoral commission said the practice is illegal.Mnangagwa has denied allegations of vote-rigging for Mugabe in the past and has promised credible elections, pledging to allow Western observers once banned by Mugabe to monitor the polls. He has also promised to accept election results even if he loses.Some said Chamisa would be careless to believe Zimbabwe's new leader."He has a solid social base. He has the backing of youths, women, students, labor and other people who are not necessarily MDC-T supporters," said Phillip Pasirayi, director of the Center for Community Development in Zimbabwe, a non-governmental organization."But he needs to be careful because the regime can go to any lengths to retain power and maintain political dominance," Pasirayi said.