Nigerian President Goodluck Jonathan's victory in the ruling Peoples Democratic Party primary ends an informal agreement that rotated the party's presidential nominee between north and south.
That deal gave northern Nigerians another four years in office to complete what would have been the second term of the late president Umaru Musa Yar'adua. As a southerner, Mr. Jonathan challenged that arrangement eight months after coming to office following Mr. Yar'adua's death.
After watching all night as nearly 4,000 ballots were counted in Abuja's Eagle Square, Mr. Jonathan accepted the nomination just past dawn, calling for unity and paying tribute to party challengers Sarah Jibril and Atiku Abubakar, who he says fought gallantly.
"I want to welcome Mrs. Jibril and his excellency Alhaji Abubakar on board so that together we can build a Nigeria of our collective interest, a Nigeria where ideas guide our dreams for a greater nation," he said. "This is a time for the party to move forward in unity to bring this country under the PDP banner."
Former vice president Abubakar was Mr. Jonathan's biggest challenger as the consensus candidate of northern leaders who opposed breaking the regional power-sharing deal.
In his appeal to delegates before their vote, Mr. Abubakar said Mr. Jonathan's disregard for party agreements shows he can not be trusted.
"That is not the kind of person with whom you would entrust the fate of this country. Our word must be our bond. But my main opponent believes in doing things simply because it is convenient," Abubakar said. "He does not seem to care if the country is thrown into chaos and anarchy as long as he remains in power. This is dangerous."
Exaggeration is always part of politics. But Mr. Abubakar's savaging of the incumbent president appeared especially personal and shows the difficulty Mr. Jonathan may have in drawing northern support in the general election. Mr. Abubakar said the country is more divided now than it was when Mr. Jonathan came to office last year.
"We cannot afford to continue to tolerate this level of incompetence and indifference. In critical situations there seems to be no one in charge," he said.
Mr. Jonathan chose not to respond to Mr. Abubakar's attack and did not directly mention the power-sharing agreement, focusing instead on a platform of improving security and the economy while fighting corruption.
"This is more than a set of policies or new ideas. It is about all Nigerians joining hands to turn the page," he said. "Together all party members, activists, and people of Nigeria can work to win the forthcoming elections at all levels. I thank you, and God bless us all. PDP! PDP!"
The ruling party has won the last three presidential elections, so Mr. Jonathan is now the frontrunner for April's vote. He faces challenges from experienced politicians in several smaller parties and could see Mr. Abubakar again in the general election if the former vice president chooses to run as the nominee of a different party.