Ibrahim Boubacar Keita is strong front-runner heading into Mali's presidential runoff vote

BAMAKO, Mali — Longtime politician Ibrahim Boubacar Keita, who many hope will hold strife-torn Mali together, heads into the presidential runoff election on Sunday as the clear favorite with endorsements from nearly all of the 28 candidates from the first round.

Whether Keita — known by his initials IBK — will win such a strong mandate across Mali, though, remains unclear in a country where northern rebels do not fly the national flag and pelted his plane with rocks on a campaign stop there.

This West African country's pivotal election is aimed at unlocking some $4 billion in aid promised by international donors after more than a year of turmoil including a coup, followed by an Islamic insurgency that swallowed up a region the size of Afghanistan and a subsequent French-led military intervention that brought thousands of foreign soldiers to Malian soil. The chaos has scattered hundreds of thousands of people — some of whom are casting ballots from refugee camps in neighboring countries.

Keita, who is running on a slogan of "for the honor of Mali," pulled in 39.79 percent of first round votes, while former finance minister Soumaila "Soumi" Cisse won 19.70 percent. It's a reversal of fortune from 2002, when the two ran for president but Cisse, not Keita, made it to the second round.

Keita's resume also includes a 2007 presidential bid as well as a wide array of government positions — foreign minister, prime minister and speaker of the National Assembly.

"He has this reputation as somebody who is strict. He doesn't shy away from a fight," said Bruce Whitehouse, a Bamako-based Mali specialist who teaches at Lehigh University. "He's this sort of old-school politician who knows how to get things done, and knows how to build alliances. I don't think anybody sees him as any kind of visionary or innovator but he may just be sort of the man who can hold things together in some basic way."

Keita, 68, has been nicknamed Kankeletigui or "a man of his word," lending a sense of reassurance and stability to the country that has been in a state of upheaval since early 2012.

Word spread and the next day everyone showed up at the ministry in buttoned up attire.

"IBK is a proud man and someone who enforces the symbol of the state," said Mohamed Sleimane, who worked with him in the 1980s at a non-governmental organization.

Keita is seen as the candidate of choice among the junta leaders who overthrew Mali's democratically elected president in March 2012. Although they ultimately handed over power to a transitional civilian government, the coup leaders are believed to still wield considerable influence.

In contrast, the other candidate, Cisse, 63, was gravely injured while trying to escape junta-linked soldiers and sought medical treatment for months in France.

Keita has won little support from Tuareg separatists in Mali's distant north, some 950 miles (1,500 kilometers) from the capital, Bamako. Rebels tried to block his campaign stop in the provincial capital of Kidal, driving pickup trucks onto the runway and later pelting his parked jet with stones.

The Tuareg rebel group signed a reconciliation with a rival rebel group late Friday.

"I am supporting IBK because he has said that he will put together a national dialogue before making a decision on the crisis, while Soumaila Cisse has already declared that he will not give autonomy to northern Mali," said NMLA official Mohamed Ousmane Ag Medoune.

If Keita does win, his strong personal profile could also help solidify his mandate, said Paul Melly, an African affairs specialist at the London-based policy institute Chatham House.