PORT-AU-PRINCE (Reuters) - Haitians vote in a presidential run-off on Sunday that international donors hope can cement in place the stability needed to rebuild the crippled nation after last year's huge earthquake.

The election presents Haiti's 4.7 million voters with a choice between a political newcomer, energetic entertainer and singer Michel Martelly, 50, and former first lady Mirlande Manigat, 70, a law professor and opposition matriarch.

It follows a chaotic first round vote on November 28 that dissolved into fraud allegations and unrest. The United Nations, which is supporting the election, says voting improvements have been made that should better ensure a clear, credible outcome in one of the world's poorest and most disaster-prone states.

"This is the first time in Haitian history that they will have a run-off election, a second round, so I think the product of this election will be a legitimate one that will have the support of the majority of the Haitian people and that alone is already an asset for the next government," Edmond Mulet, the U.N.'s top official in Haiti, told Reuters in an interview.

U.N. blue-helmet peacekeepers will be helping Haitian national police protect around 11,000 polling points around the Caribbean state, which desperately needs a capable leadership and government to steer a post-earthquake reconstruction that requires billions of dollars of foreign assistance.

U.N. Secretary-General Ban Ki-moon and other international leaders appealed for a calm, transparent vote.

Weighing on many Haitians' minds as they cast their ballots will be the reappearance of a political heavyweight from the past, former President Jean-Bertrand Aristide, who arrived back from exile on Friday.

The return of the charismatic left-wing populist and former Catholic priest who still commands a big following in Haiti was opposed by the United States and United Nations as potentially disruptive to the polls. But Aristide is not a candidate and aides have said he will stay out of politics.

Although Aristide, who was driven into exile by a 2004 rebellion, has not clearly endorsed any candidate, many voters have been trying to interpret who he favors in what is expected to be a close-fought run-off. Nevertheless, recent opinion polls have shown Martelly slightly ahead of Manigat.

Mixed in with banners welcoming Aristide, the dueling slogans of the rival candidates are plastered on walls and posters in Port-au-Prince's earthquake-damaged streets.

Martelly's "Tet Kale" slogan, a Creole play on words that refers to his shaven head and also means "all the way" to convey his promise of forceful change, contrasts with Manigat's more homely "Banm Manman'm" (Give me Mummy) slogan that seeks to bolster her image of experience and responsibility.


While most agree Haiti urgently needs to break with its past of poverty, bad government and violence, the debate has focused on which of the candidates can best achieve this.

"We need change. I didn't vote last time, but I will this time," said 26-year-old Benchy Joseph as he sat with friends near the shattered ruins of Port-au-Prince cathedral, amid streets still clogged with quake rubble, refuse and sewage.

"Give me Mummy," he said, indicating he would vote for Manigat, who became a senator and a first lady in 1988, when her husband Leslie Manigat won the presidency. They were both forced into exile by a coup four months later.

But Joseph's mother, Madeleine Joseph, preferred political neophyte Martelly. "I would like to try a candidate who has not been in power before," she said.

Others, reflecting Aristide's image as a champion of the poor, said if he were on the ballot they would vote for him.

Under Haiti's election law, the Provisional Electoral Council is due to announce preliminary results from the run-off on March 31, with final results being confirmed on April 16.

The U.N.'s Mulet acknowledged this long wait for results ran the risk of rival camps stirring up supporters with noisy claims of victory or fraud -- such claims in the first round triggered street protests. But he was confident U.N. forces supporting Haiti's police could control the situation.

Some analysts said that even without Aristide's return, ensuring a smooth electoral process in Haiti was a tough job.

"The international community has worked hard and done its best to put things in order, but the task has been formidable, and a lot can still go wrong. There is little confidence in electoral authorities and continued concern about fraud and possible violence," said Michael Shifter, president of the Inter-American Dialogue think tank in Washington.

(Editing by Jackie Frank)

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