Authorities deployed a 42,000-strong security force, made up of the police and military, to try and prevent a repeat of the chaotic violence by armed groups that marred last month's first round vote.
Election officials were concerned that fresh attacks would dampen turnout for the runoff, after several incidents forced about a fifth of polling stations to close during the July 29th preliminary poll — mostly in the lawless central region. In northern Mali, jihadists killed the head of a polling station during an attack on the facility.
Just 40 percent of voters took part in the first round, which saw Keita win 41 percent support against nearly 18 percent for Cisse, a former finance minister.
"We traveled the whole country and we noticed everywhere a strong desire for change," said Cisse. "Malians want change, they want another future and hope. This is why I am happy to be here. I am happy because I am confident in the vote, which takes place today."
Read more: Malians want stability and security, former minister says
Keita wins new supportersDespite Cisse vowing to win over voters in time for Sunday's runoff, analysts said he has failed to unite the opposition behind him, after the most popular first-round challengers backed Keita.
The president is seeking a second term after beating Cisse in a 2013 election.
But the 73-year-old Keita faces severe criticism over his failure to dampen a wave of jihadist bloodshed and ethnic violence.
The main opposition has also accused his government of rampant corruption and voting fraud in July.
Militants regroupConcerns are mounting that militants — including those linked to al-Qaida and the Islamic State (IS) armed group — have regrouped since a French intervention in 2013, and are now expanding their influence across the desert north and into the fertile center.
More than 930 militant attacks were recorded in the first half of 2018 by the civil society website Malilink, almost double that for the previous year, and triple 2015's figures.
Read more: Attack on Sahel counterterror force puts jihadists in focus
Jihadists are also stoking inter-communal conflict, leading to tit-for-tat killings along ethnic lines, which have claimed hundreds of civilian lives this year.
Mali's leaders face pressure to strengthen a 2015 peace accord with Tuareg rebels, who had previously joined forces with Islamist groups to seize large swathes of territory.
Meanwhile, security services said on Saturday they had disrupted a plot to carry out "targeted attacks" in the capital Bamako ahead of the runoff. Three people were arrested.
mm/ng (AFP, Reuters)
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