"The saying goes that when the going gets tough, the tough get going," a smiling Mahama said in a November interview
Mahama, now 58, came to power in 2012 after narrowly defeating the New Patriotic Party (NPP) candidate Nana Akufo-Addo, who is also running in Wednesday's presidential election.
But his government went on a spending spree, causing Ghana's political titan and former president Jerry Rawlings to describe Mahama's ministers as "babies with sharp teeth."
The global commodity rout hurt Ghana -- a global exporter of oil, gold and cocoa -- but the ballooning debt made things much worse.
With stuttering electricity, double-digit inflation and a depreciating cedi, this West African nation was forced to turn to the International Monetary Fund for help.
Corruption scandals have plagued his government, but Mahama, an affable statesman who is popular with the public, has worked to stay above the fray with his slogan "Putting people first."
"The saying goes that when the going gets tough, the tough get going," a smiling Mahama said in a November interview.
In his eloquent 2012 autobiography, "My First Coup d'Etat", Mahama describes life in Accra's elite boarding school juxtaposed with going back to the northern village where his family is from, climbing mango trees and hunting squirrels with slingshots.
"Bole was not on the national grid, but we had a little diesel generator, which meant ours was the only house in town with lights," Mahama writes.
Born to the son of a minister overthrown in a 1966 coup -- which he describes as an "unspeakable period of violence" -- Mahama later graduated from university with a history degree.
He went to Moscow in 1988 for a post-graduate degree in social psychology, where he grew "more and more disillusioned with socialism, realising that Ghana has to find its own transformative way, away from ideological dogmas."
In 1996, he joined the NDC, where he later served as minister of communications.
Mahama became vice-president of Ghana in 2009 under President John Atta Mills.
When Mills died unexpectedly in 2012, Mahama became president and won the election that year.
"JM", as he's called by those close to him, is a member of the Assemblies of God, "a multi-faith family consisting of Christians and Muslims".
Mahama says he's a big fan of Afrobeat, music originating from Nigeria that's an intoxicating fusion of blues, jazz and funk.