By Joseph Winter
The opposition is divided but remains confident
Saturday's elections are the most exciting Zimbabwe has seen since those at independence 28 years ago which brought Robert Mugabe to power.
For the first time since a credible opposition was formed eight years ago, campaigning has been generally peaceful and candidates challenging Mr Mugabe have been able to operate in rural areas, where the majority of voters live.
Although the president's slogan is the menacing "Behind the fist", his militias - the war veterans and "green bombers" - have generally left the opposition alone, unlike in previous elections.
This could be because of the entry of a presidential challenger from within the ruling Zanu-PF party.
Former Finance Minister Simba Makoni is generally well regarded by both Zanu-PF supporters and opposition sympathisers.
Some say he entered the electoral race too late to have a realistic chance of winning and that veteran opposition leader Morgan Tsvangirai is Mr Mugabe's main rival.
But Mr Makoni's announcement six weeks ago that he would stand as an independent candidate created an immediate buzz of excitement, leading many people who had given up hope that elections could make a difference to register to vote.
"He's the new kid on the block," one Harare resident told the BBC News website.
"He's the only one who can defeat the incumbent, as he has more chance of carrying the rural areas."
To win the keys to state house, a presidential candidate needs 50% of the vote, so a second round is a distinct possibility.
Bread is sometimes only available on the black market
The anti-Mugabe vote would surely unite for a run-off, meaning the incumbent's best chance of victory comes this Saturday.
But the Makoni factor is not clear.
Some cynical Zimbabweans, used to Mr Mugabe using a full arsenal of tactics to remain in power, suspect Mr Makoni could have been sent to split the anti-Mugabe vote.
Others, however, say he will instead divide the Zanu-PF vote.
In some rural areas of Mashonland East, which have generally voted for Mr Mugabe in the past, some Zanu-PF parliamentary candidates are urging their voters to back Mr Makoni in the presidential race.
Political analyst John Makumbe told the BBC that 50-60% of rural Zanu-PF supporters will back the former finance minister.
Mr Makoni's camp says that a majority of senior Zanu-PF leaders secretly support him but only one party heavyweight has done so in public.
Former Interior Minister Dumiso Dabengwa is highly regarded in Matabeleland, where a splinter group of the MDC is also backing Mr Makoni in the presidential race.
But Mr Mugabe has not been popular in Matabeleland since his forces ruthlessly suppressed an uprising there in the 1980s, so he does not have too many votes to lose there.
During the campaign, Mr Tsvangirai has been drawing the biggest crowds.
1: Mashonaland West
2: Mashonaland Central
3: Mashonaland East
7: Matabeleland South
8: Matabeleland North
That obviously does not necessarily translate into the most votes on election day - some may be attracted by promises of free T-shirts or food hand-outs, while others may not be registered to vote - but the MDC has gained confidence.
Even opposition activists had criticised Mr Tsvangirai and thought Mr Mugabe had outmanoeuvred him in recent years but he is still better known around the country than Mr Makoni.
And for the first time, Mr Tsvangirai has been able to campaign in Mr Mugabe's heartlands of Mashonaland West and Central.
The economic crisis has not spared these areas and the redistribution of land which has ensured voters' loyalty in the past has not led to the higher living standards Mr Mugabe had promised.
People are increasingly blaming the government for the lack of basic goods in the shops and money in their pockets - messages which Mr Tsvangirai has been hammering home.
"I have no doubt that we have overwhelming support," he told the BBC's Network Africa programme.
But a few weeks' campaigning may not be enough to overcome the effect of years, during which the voice of the opposition was hardly heard in rural areas.
Mr Mugabe blames Zimbabwe's problems on a Western plot to remove him from power.
Dead people can vote
And Mr Mugabe may well have other tricks up his sleeve.
"It's not a question of who votes, it's a question of who counts and who announces," one Zimbabwean analyst told the BBC.
The army could hold the key to Robert Mugabe's future
Mr Tsvangirai has a long list of electoral complaints and fears that the Zimbabwe Electoral Commission will do the ruling party's bidding.
The government has denied that it is planning to rig the poll.
But Mr Tsvangirai says there are thousands of dead people on the voters roll, who might nevertheless vote Zanu-PF, while there are fewer polling stations in his urban strongholds than in Mr Mugabe's rural bases.
Local chiefs have also been used to ensure rural people vote for the status quo - the president of the council of chiefs has admitted that food aid is denied to opposition supporters.
"This is the crisis we faced in 2002 and 2005," Mr Tsvangirai said.
"Although we had the support of the people, we didn't manage to win the election."
But he and others argue that the more people vote against Mr Mugabe, the more difficult it will be for the outcome to be altered.
This is where Mr Makoni's entry into the race could prove to be most significant.
Mr Makumbe says that senior military officials and agents from the Central Intelligence Organisation, Zimbabwe's feared secret police, back Mr Makoni and may refuse to rig the poll on behalf of the president.
OPPOSITION POLL CONCERNS
Surplus ballot papers printed
Tens of thousands of "ghost voters"
Police allowed inside polling stations
More polling stations in rural areas
State media bias
Food aid only given to Zanu-PF supporters
Chiefs used to campaign for Zanu-PF
"It is not a question of whether Mugabe will try to rig, it is a question of whether he will be allowed to," Mr Makumbe says.
Mr Mugabe has been trying to shore up his support by distributing agricultural equipment during the campaign.
Just three weeks before the elections, he also approved new legislation which paves the way for foreign-owned firms to be forced to give up a majority of their shares to black Zimbabweans.
Some see this as an electoral bribe for businessmen, in the same way that the redistribution of white-owned land was used in rural areas.
Mr Mugabe also passed huge pay raises for teachers and civil servants in the run-up to the polls but was dismayed as these were quickly wiped out by inflation, which is running at 100,000 a year - the world's highest rate.
With the result of the election so uncertain, people are once more starting to ask whether Mr Mugabe would accept defeat.
Indigenisation and Empowerment Minister Paul Mangwana told the BBC that he would, pointing to the president's acceptance of his only electoral set-back to date - a 2000 constitutional referendum.
Simba Makoni has changed Zimbabwe's electoral dynamics
"He is a democrat," Mr Mangwana told the BBC.
But those opposition activists who have been beaten, tortured and raped by Mr Mugabe's supporters in recent years would disagree.
Some raise the spectre of the ethnic and political violence which followed Kenya's disputed elections being repeated in Zimbabwe.
The government has been able to easily put down previous protests by opposition supporters because of the loyalty of the security forces.
But as the economic situation gets ever worse, that loyalty can no longer be taken for granted.
If the army chiefs rumoured to support Mr Makoni told the president he had lost the vote, that is one verdict he would have little option but to accept.
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