Zimbabweans will vote on a new draft Constitution – a key reform ahead of new presidential polls that should end the power-sharing deal.
Morgan Tsvangirai pulled Zimbabwe from chaos by forming a unity government with President Robert Mugabe, and still struggles to guide the country toward democracy from within his narrow corridors of power.
The new presidential polls in July 2013 may just see him become only the second president since the country's independence in 1981.
Tsvangirai, the founder of the Movement for Democratic Change (MDC), emerged in the late 1990s as a powerful political force when he headed the country's largest labour federation, spearheading national strikes against Mugabe's economic policies.
After years in the opposition, he stood poised to claim the presidency in 2008 elections, but abandoned the run-off against Mugabe to stem a wave of violence that killed more than 200 of his supporters.
At the time, hyperinflation had pushed the economy into freefall, more than half the nation needed food aid, and a cholera epidemic was swirling.
Under intense regional pressure, Tsvangirai and Mugabe formed a unity government in February 2009, with the MDC taking over most ministries dealing with the economy, while Mugabe's ZANU-PF retained the security forces and the mines.
Tsvangirai became Prime Minister under Mugabe.
The result has been a rocky coalition, with the two rivals often steering the country in opposite directions, especially when it comes to implementing the democratic reforms required under their unity pact.
"The progress that has been secured so far has been far from satisfactory, especially on political reforms," Tsvangirai said in 2011.
"However, you will agree with me that there has been notable progress ever since the consumation of this government, and that progress is in the social sectors."
Zimbabwe's economy has stirred back to life. Food supplies are more reliable and once-shuttered hospitals are back open.
But Tsvangirai battles to exert his influence. His supporters, even his ministers, still suffer routine arrests and harassment.
His personal scandals – two very public divorces – have dented his popularity.
Tsvangirai claims to have been the target of four assassination attempts, including one in 1997 when he said assailants tried to throw him out of his office window.
Despite the violence directed at him and his party, the 60-year-old has used his persuasive speaking skills to keep his supporters focused on non-violent activism for "a new Zimbabwe."
"I have done my part to promote reconciliation in this country. Even after winning the election, I have compromised for the sake of Zimbabwe," he once told a rally.
But four years after formation the unity government has been hampered by disagreements over key economic policies and the slow progress of human rights reforms.
He grew up in the eastern district of Buhera, and was forced by poverty to leave school early and earn a living to enable his younger siblings to get an education.
Unlike most of Zimbabwe's politicians, Tsvangirai did not take part in the Chimurenga liberation war against white colonial rule.
Born in Gutu, south of the capital Harare, he was the eldest of nine children and the son of a bricklayer. He was 28 when Zimbabwe won independence from Britain in 1980. Tsvangirai's rise to power came with intense personal loss.
Just three weeks after taking office, his first wife Susan died in a car crash that also left him in hospital.
He has been detained twice for his political activism and was twice cleared of treason charges.
In March 2007, he was among dozens of opposition activists who were assaulted as they tried to stage an anti-government rally, suffering head injuries.
"Yes, they brutalised my flesh. But they will never break my spirit. I will soldier on until Zimbabwe is free," he said in a message from his hospital bed. – AFP