(CNN) -- President Robert Mugabe, who has ruled Zimbabwe with an iron fist for nearly three decades, faces his toughest challenge yet in this weekend's general elections.
Zimbabwean President Robert Mugabe campaigns in the capital of Harare last week.
Voters go to the polls Saturday in simultaneous presidential, parliamentary, senate and council elections. Mugabe, 84, is seeking a sixth consecutive term as president of the southern African nation.
Mugabe faces three opposition candidates, two of whom have a good chance of winning. Mugabe's regime may be on shaky ground amid allegations of corruption and a failing economy.
Zimbabweans are the poorest they have ever been since the nation became a democracy. Unemployment is estimated at around 80 percent, inflation is more than 100,000 percent, and hundreds of thousands are fleeing the country to earn more elsewhere than they would back home.
He was once respected as a liberation hero, but observers now criticize him for repressive tactics and corruption, and blame him for the country's dire economic state.
The Movement for Democratic Change, or MDC, is the main opposition to Mugabe's ruling Zanu-PF party. But a split in 2006 severely weakened the MDC, and the party's two factions back different candidates.
One faction supports MDC founder Morgan Tsvangirai, who led hotly contested challenges against Mugabe in 2000, 2002 and 2005.
This week, Tsvangirai had to cancel campaign rallies after the Zimbabwean government impounded a helicopter that was to carry him around the country, according to the owner of the copter charter company.
The other MDC faction backs Simba Makoni, Mugabe's former finance minister, who was expelled from the Zanu-PF after announcing his bid to unseat the president.
In what critics labeled a vote-buying exercise, Mugabe recently increased the salaries of the police, army and teachers and also handed out machinery to black farmers. Zimbabwean officials deny the moves had anything to do with the election.
Opposition: Millions of extra ballots printed
The MDC said Sunday it had discovered evidence that Mugabe intends to rig the elections in his favor. Watch evidence of dead voters still on the rolls »
Tendai Biti, the MDC's secretary-general, said that leaked correspondence from Zimbabwe's electoral commission showed it had asked the company printing paper ballots to print 9 million. The country has an electorate of 5.7 million registered voters, Biti said.
Also, Biti said, the commission requested 600,000 postal paper ballots for soldiers and police officers. The number of soldiers and police in Zimbabwe adds up to no more than 50,000, he said.
"Remember, when they stole this election away from us the last time, they stole it with 350,000 votes," Biti said. "Six-hundred thousand is double insurance."
The United States this week warned of a possible unfair election, citing inaccurate voter rolls, the extra ballots for soldiers and police, intimidation of the opposition and the absence of independent observers.
The New York-based Human Rights Watch has warned the elections were likely to be "deeply flawed." It said the electoral commission is partisan toward Zanu-PF and lacks both expertise and resources to run the elections properly.
A Zimbabwean official criticized the report, saying the elections can't be judged beforehand.
The Zimbabwean government this week denied CNN permission to cover the elections. It gave no reason for the decision.
Journalist: Mugabe intends to stay in power till death
The government also has handpicked election observers perceived as sympathetic to the ruling party.
After winning the last elections in 2005, Mugabe said he wanted to stay in power until he was 100 years old. The comment was interpreted as a joke, but many Zimbabweans didn't find it funny.
"What Mugabe says is normally what he intends to do," said Martin Meredith, who spent years covering Africa for British newspapers and has written biographies about Mugabe. "OK, he might not remain alive until 100, but he intends to remain in power until he dies."
Mugabe has been in power for so long that many young Zimbabweans have known no other leader.
After fighting in the civil war against the white Rhodesian government, Mugabe was part of the independence negotiations. He became Zimbabwe's first black prime minister and was lauded as a liberation hero -- someone of fierce intellect who presided over an African success story.
But nearly three decades later, Mugabe has consolidated his rule over all aspects of Zimbabwean life.
Soon after Mugabe came to power, his government launched a campaign to crush opposition in an area called Matabeleland. The massacre and beatings of thousands of civilians was little reported at the time and is still barely condemned.
Farms seized; slums razed
In 2000, Mugabe ordered the controversial seizure of commercially white-owned farms. He gave the land to black Zimbabweans who, he said, were cheated under colonialist rule.
White farmers who defied their eviction notices were jailed.
Five years later, Mugabe launched Operation Clean Out the Trash in which he razed slum areas.
Mugabe's land redistribution policies caused food production and agricultural exports to drop drastically and sent Zimbabwe into an economic freefall. In a country once viewed as southern Africa's breadbasket, it is now difficult to get basic food supplies.
"People are having to go to neighboring countries like South Africa and Botswana to buy flour, sugar,and cooking oil," said journalist Brian Hungwe.
Empty supermarket shelves are a common sight. People dig holes in the ground for filthy, contaminated water and turn to the black market for fuel.
Among the many who have fled Zimbabwe are professionals reduced to a life of odd jobs.
"As long as I'm getting money," said Blessing Tembo, a Zimbabwean engineer who takes whatever work he can find, whether it's cleaning someone's yard or carrying goods.
Tembo spoke from Francistown, Botswana, a border town that has absorbed thousands of Zimbabwean refugees looking for jobs, food and health care.
Nurses in Francistown say so many pregnant Zimbabweans are flooding Botswana that they're delivering more Zimbabwean babies than local ones.
"There are few doctors," Lydia Chishike, a pregnant Zimbabwean, said in Francistown. "Sometimes you go for a checkup, and there will be no doctors. Things are not in good condition there."
Economic solution includes $10 million bill
Zimbabwe has introduced measures to try to stem the country's decline, including the printing of more money in higher denominations. The latest is a $10 million bill.
Strict price controls punish businesses that price goods above levels set by the government, and a new bill forces foreign-owned businesses to give controlling interests in their operations to black Zimbabweans.
Once revered for offering its citizens some of the best education and health care in Africa, Zimbabwe has one of the lowest life expectancies in the world and education is becoming a luxury.
Mugabe denies mismanagement and instead blames economic woes on the West.
"They have even interfered with international organizations of which we are a member -- the World Bank and IMF [International Monetary Fund] -- which cannot extend any facility to Zimbabwe unless America and Britain say so," Mugabe has said.
In a CNN interview in 2000, Mugabe offered insight into his thinking on elections and power.
"When you go to elections it is not necessarily that of including every party in your Cabinet," he said. "You go into elections competing with each and every other group in order to win. Win and govern." E-mail to a friend