EBOLA NOT A FACTOR SO FAR

The issue that has not yet played an important role is Ebola, rampant in some other West African states. A mixture of luck and impressively decisive action has meant Africa's most populous country was able to avoid a potentially devastating epidemic after a Liberian brought it to the megacity of Lagos, but the virus could still come back to plague Nigeria, with unpredictable political consequences.

Jonathan's assumed decision to run has widened a divide between elites in Nigeria's south and north because of a feeling in the north that it is still their "turn" to rule.

The Source Yahoo says that it makes violence likely, especially if the poll is close. In 2011, more than 800 were killed and 65,000 displaced in three days of violence after Jonathan beat Buhari in the poll.

If Buhari, now 71, gets the ticket but loses the election again, his supporters may have less reason to end the mayhem so quickly if they sense he has missed his last chance.