Will Ross of the BBC takes a look at issues surrounding Nigeria's General election-
In Nigerian elections, the incumbent always wins. But so far this campaign has been different from all others and this Saturday's poll is a real contest.Not only has President Goodluck Jonathan haemorrhaged support since he comfortably won in 2011, the "change" chanting opposition has thrown its combined weight behind one candidate - former military ruler, Muhammadu Buhari.
In a country where opinion polls can be trusted about as much as a politician's promise, it is hard, even foolish, to predict the outcome.
With control over Africa's largest economy at stake - this is a country where multi-billion dollar corruption scandals come and go - the campaigns have been toxic with both the ruling People's Democratic Party (PDP) and opposition All Progressives Congress (APC) hurling abuse at each other.
'Shameless'In this diverse nation of immense potential, regional and religious divisions have been exposed. The two main candidates are from different religions from opposite ends of the country - Mr Jonathan is a Christian from the south and Gen Buhari a Muslim from the north.
The hate speech seemed to reach a dangerous nadir earlier this month when the president's wife, Patience Jonathan, was filmed at a campaign rally telling a crowd: "Anyone that comes and tells you 'change', stone that person."
Her spokesman was later quoted in the local media saying she was a woman of peace.
"Shamelessly you will discover politicians, against the electoral law, distributing money," says Bawa Abdullahi Wase of the Nigeria-based Network For Justice rights group.
He says a candidate wishing to get a seat in the House of Representatives needs a minimum of $1m (£670,000) for the campaign. For a Senate seat the war chest must be even larger.
These are the most expensive elections ever held in Africa and Nigerians are left guessing how much of the campaign money has been looted from the public purse by power-hungry men and women on both sides of the political divide.
'Bribes'"When they get into office, instead of concentrating on offering services to the people like electricity, water, roads and education, they amass the wealth of the total budget because they know for the next election they will have to spend more than they've spent in this election," Mr Wase adds.
As well as cutting expensive deals, the main political parties have been dishing out sacks of rice to voters in an effort to influence the outcome.
"I will collect it, but I will vote for whoever I want," says Peter Ayas, standing in a tailor's shop in the commercial capital Lagos's Obalende suburb. He adds that he found the bribe an insult.
Goodluck Jonathan in focus:
- Has a penchant for fedora hats
- Regular church-goer
- Middle name, Ebele, means "God's wish"
- Fond of saying he never had shoes as a child because of poverty
- Told journalists in 2012 that he would not declare his assets because he did not "give a damn about it, even if you criticise me from heaven"
- Denied reports in 2014 that his net worth is about $100m (£62m)
"The gap between the rich and the poor is too wide. It is only during the election that you see the rich coming down to interact with the poor, to get their votes," Mr Ayas tells me over the din of generators due to the appalling electricity supply.
'International reputation'A six-week delay in the vote has meant the electoral commission is now better prepared - some analysts believe it would have been an utter shambles had the vote gone ahead on 14 February.
There are still concerns over whether the elections will take place, as many Nigeria watchers believe the ruling party will not risk facing the electorate unless victory is certain.
Muhammadu Buhari in focus:
Military ruler of Nigeria from 1984 to 1985
Deposed in a coup
Poor human rights record
Seen as incorruptible
Disciplinarian - civil servants late for work had to do frog jumps
Muslim from northern Nigeria
Survived an apparent Boko Haram assassination attempt
Profile: Muhammadu Buhari
Mixing religion and politics
Serious about tackling corruption?
In a letter this week, UK Prime Minister David Cameron urged Mr Jonathan to ensure that the elections go ahead as scheduled, warning that failure to do so "would risk national security and stability, and adversely affect Nigeria's international reputation".
"There is still a suspicion that neither party appears well-suited to the trauma of defeat and that what Nigeria needs after the dust settles on this election is not just an effective government, but an effective opposition," says Anthony Goldman, a Nigeria expert who heads the London-based PM Consulting firm.
Whether this important period in Nigeria's history is peaceful will partly depend on the behaviour of the politicians and their hired thugs, as well as the determination of militant Islamist group Boko Haram to disrupt democracy.
The official reason for the election delay was the insecurity in the north-east.
Considering the massive loss of life - campaign group Human Rights Watch says the insurgents have killed 1,000 people this year alone - it seems inexcusable that a robust military offensive was not launched months, even years, earlier.
A pre-election regional assault has turned the tide against the jihadists but as a disrupted rather than decimated force they still pose a significant threat.
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Media caption Peter Okwoche asked the people of Port Harcourt which candidate - and their hat - they will choose.
It is unclear how much voting will take place in the battered north-east, where 1.5 million people have fled their homes. A low turn-out would favour Mr Jonathan as it is an opposition stronghold.
Then there is the threat of further bomb attacks even outside the north-east - in recent years cities like Kano, Kaduna, Jos and Abuja have been targeted in bombings blamed on Boko Haram.
'Memories of civil war'
The oil-rich Niger Delta, where the incumbent is from, is another flashpoint. Political rivalries in Rivers State threaten to boil over and some former militiamen have promised chaos should Mr Jonathan not win.
There is a deeply entrenched culture of impunity in Nigeria when it comes to electoral violence and it seems that suits many politicians.
"In the past, most people who are implicated or indicted in the election violence go home scot-free. There are no trials," says Tony Ojukwu of Nigeria's National Human Rights Commission.
"After the last election [when at least 800 people were killed] the reform panel recommended that an election offences tribunal should be set up. But, of course, you know this is not in the interests of the politicians as they are the major violators so they never set up that panel," adds Mr Ojukwu.
Many Nigerians cannot wait for this drawn-out tense period to be over.
"I pray every day but this morning I prayed hard for Nigeria," says Tomiwa who works for an online business in Lagos.
The night before she had watched a film set during Nigeria's civil war, which ended in 1970 with the military putting down an attempt to create the breakaway Biafra state.
"I saw so many parallels with the current situation in Nigeria, it terrified me," she said.