The February 14 vote looks set to be Nigeria’s least one-sided since the end of military rule in 1999.
Jonathan has yet to formally declare his intention to run for a second term, but he has been endorsed as sole candidate by the board of his ruling People’s Democratic Party (PDP).
In a speech to mark Independence Day, he praised the armed forces in their fight against a 5-year-old Islamist insurgency.
“Our security forces continue to engage the terrorists in battle,” Jonathan said in a broadcast on state TV to mark 54 years of independence from Britain.
“Driven by patriotic zeal, they are turning the tide … inflicting devastating blows at the heart of terror,” he said.
Nigeria’s overstretched military has been repeatedly routed by the insurgents fighting for an Islamic state in the religiously mixed country, and some soldiers have been court martialled and sentenced to death for desertion.
The army has come under heavy criticism for failing to protect civilians from the rebels, epitomised by the kidnapping more than 200 girls from an unguarded secondary school in April.
But security sources say Nigerian forces backed by fighter jets have inflicted heavy losses on Boko Haram in the past few weeks, as the insurgents sought to hold on to territory they seized in the northeast of Africa’s top oil producer.
Last week the military said more than 130 Boko Haram Islamist fighters had surrendered to Nigerian forces, and a man posing as the group’s dead leader Abubakar Shekau in numerous videos had been killed.
Jonathan’s probable candidacy has divided the political elite, with some northerners saying it breaks an unwritten rule that power should alternate between the largely Muslim north and mostly Christian south every five-year presidential term.
Despite defections from his party this year, multibillion dollar oil corruption scandals and negative publicity over the schoolgirls’ kidnapping, Jonathan looks strong, as the main opposition coalition bickers over who will lead it.
Jonathan listed his achievements, which included privatising the moribund power sector — widely seen as his biggest achievement, though it has yet to end chronic blackouts and some of the companies that bought assets are in financial trouble.
He also mentioned greater participation of local companies in the oil sector, although some have been implicated in the corruption scandals dogging Jonathan’s administration. He touted the fact that Nigeria is now Africa’s biggest economy, although that occurred only because of a GDP recalculation.
The opposition All Progressive’s Congress (APC) holds a primary in December, which so far is shaping up to be a contest between former vice president Atiku Abubakar and former military ruler Muhammadu Buhari, who lost against Jonathan in 2011 polls.
“For the first time, the credible opposition in Nigeria has come together,” Buhari said during a campaign speech on Tuesday.
Buhari — deposed in a coup in 1985 — is popular in the north and widely recognised as one of the few Nigerian leaders not to have gained from the widespread corruption.
The APC is campaigning on corruption and better security.
Buhari said Nigeria was “saddled with Nigeria with … a perilous security situation, extensive and almost unmanageable corruption and … pervasive lawlessness”.