Mali's presidential front-runner has ended his campaign promising to restore peace to the West African country reeling from a coup and an uprising that led to French military intervention.
Ibrahim Boubacar Keita, 68, a former prime minister with a reputation for toughness, won last month's first-round ballot with nearly 40 percent of the vote but fell short of an outright majority to avert a second round.
He faces Soumaila Cisse, a former finance minister, in Sunday's run-off.
The first round attracted 27 candidates and Keita, popularly known as IBK, has secured the endorsement of 22 of the 25 losing candidates.
Cisse, 63, the head of the West African monetary union (UEMOA), took just 19 percent of the first-round vote with promises to improve education, create jobs and reform the army.
Once seen as a model for democracy in turbulent West Africa, Mali was rocked by violence last year when al-Qaeda-linked rebels capitalised on the coup to seize control of the vast desert north, where they imposed a harsh version of Islamic law.
French pullout plan
France, Mali's former colonial master, sent troops in January, destroying the enclave, which it said threatened the West.
Despite ongoing tensions with Tuareg separatists in northern Mali after a ceasefire last month, France is looking to pull out most of its remaining 3,000 troops.
"My first priority, will be to pursue ... a lasting peace deal," Keita told French news channel France 24. "That will be a real peace, not a false one."
Sunday's election should unlock some $4bn in aid and allow France to hand responsibility for maintaining security to a 12,600-strong UN peacekeeping mission being deployed.
With the end of campaigning coinciding with the Eid al-Fitr festival to mark the end of Ramadan, the Muslim month of fasting, both candidates cancelled their main political rallies.
Keita has captured the popular mood by avoiding outspoken criticism of the coup leaders, earning the tacit blessing of the military. He has also successfully courted Mali's powerful religious leaders, several of whom have endorsed him.
Critics say Cisse, who condemned the coup, defends a corrupt political class that dragged Mali into the current crisis by ignoring rising frustration at poverty.
The majority of Mali's 16 million people live on less than $1.25 a day.
Cisse rejects the claim, saying he is a defender of democracy. After challenging the result of the July 28 election, alleging systemic fraud, he has vowed to accept the outcome of the second round.
"I call on you all to vote on Sunday. Trickery will not triumph," Cisse told cheering supporters at a rally.
With hundreds of anti-government fighters killed and those who survived scattered by the French-led offensive, the most pressing challenge facing the new president will be peace talks with the Tuareg MNLA separatists.
A ceasefire that allowed voting in northern Mali obliges a new government to open talks within 60 days.
Sunday's vote comes as rebel factions from the north have reached a reconciliation agreement following talks in neighbouring Mauritania.
The agreement announced late on Friday is between secular Tuareg rebels and Arab fighters. Both operate in Azawad.
The MNLA, the High Unity Council of the Azawad and the Arab Movement of the Azawad all said they had "decided to open a new page in the history of Azawad based on tolerance".