Nigerians are so used to the idea that an
incumbent should win presidential elections
that President Goodluck Jonathan's failure
to beat Gen Muhammadu Buhari needs
some explaining.

Here are five reasons why
the opposition won:


1: Harder to rig
Past elections have been marred by serious
irregularities and suspicions of rigging. In 2007
observers said the presidential poll was not
"credible". In 2011 the vote was considered to
be better run but observers said that rigging
and fraud still took place.
This time the electoral commission took more
steps to prevent rigging, including new
biometric voters cards.
Also President Jonathan's party, the People's
Democratic Party (PDP), had lost control of
some key states which meant it could not
control the electoral process there.


2: Boko Haram and security
The Nigerian army has made some recent
gains against Boko Haram, but not enough
to convince Nigerians
The election took place against the background
of an Islamist insurgency in the north-east of
the country. The Boko Haram militant group
has killed 20,000 people and forced some three
million others from their homes and President
Jonathan was criticised for not getting to grips
with this.
The poll was delayed for six weeks to give time
for the security situation to improve, but even
though most areas controlled by Boko Haram
were recaptured, it seems to have come too
late for many people.


3: United opposition, crumbling PDP
The extra six weeks of vigorous campaigning
by the PDP was not enough to halt the slide
in the party's fortunes
The PDP has been described as an election-
winning machine. When it was created it united
a northern elite with leading politicians from
the south, but that alliance has broken up and
the party lost some key figures. Even former
President Olusegun Obasanjo came out against
Mr Jonathan.
At the same time, the opposition managed to
unite under the All Progressives Congress (APC)
banner. The last six weeks of desperate and
dirty campaigning, in which the APC responded
in kind, was not enough to turn the tide.


4: Economy
Nigeria's economy is growing but the wealth
is not being spread around
Nigeria is Africa's biggest oil producer and its
largest economy, but many fail to feel the
benefits with nearly half the population living
below the poverty line. Continued corruption is
seen as partly being to blame.
National income is due to grow by more than
5% this year and next year, but people did not
seem in the mood to thank Mr Jonathan for
this.


5: Time for a change
APC supporters chanted "change" wherever
they went and it seems to have caught the
mood. The PDP has been in power since the
end of military rule in 1999, and 2015 is the
year that Nigerians decided that someone else
should have a go at sorting things out.
President-elect Buhari now has to prove he
really can change things.