An estimated one-third of government spending goes towards Chad's vaunted army, a dependable regional policeman and the pride of the people. But a taste of stability, and oil money, has Chadians wanting more.
Muhammadu Buhari is the first opposition candidate to unseat an incumbent in a presidential election. He has vowed to strike hard at Islamist militants in northern Nigeria.
Nigeria's Boko Haram pledged allegiance last week to the self-proclaimed Islamic State, which is fighting for control of the Iraqi city of Tikrit.
The militant Islamist group killed 68 in Njaba, but has suffered setbacks in some areas after Nigeria teamed up with other West African countries to launch air and ground attacks.
Nigeria-based Boko Haram militants attacked neighboring Chad for the first time, killing several civilians in a border town. Chad has targeted the Islamist insurgency as part of a regional coalition.
Militants had stolen arms, ammunition, and armored vehicles during an attack on a multinational military base last month. Their recovery by the Nigerian military marks the latest setback Boko Haram has experienced in recent days.