By Kieran Murray
PORT-AU-PRINCE, Haiti, Feb 7 (Reuters) - Haitians vote for a president and a new chance at democracy on Tuesday although many fear rival armed gangs could wreck the election.
Exactly 20 years after the dictatorial rule of Jean-Claude "Baby Doc" Duvalier crumbled, Tuesday's vote offers some hope for an end to the coups and instability that have crippled Haiti since then.
In the most recent uprising, former allies and long-time enemies forced former president Jean-Bertrand Aristide to flee two years ago.
A new round of fighting, however, could plunge the poorest country in the Americas into even deeper chaos.
"People are exhausted by this instability, the lack of security," Gerard Le Chevallier, the top U.N. official overseeing the election, told Reuters on Monday.
Front runner Rene Preval draws support from the miserable urban slums and rural areas where his mentor Aristide was strongest.
Preval was also president from 1996 to 2001, an era of relative calm, and he is Haiti's only elected leader to end his term and hand over power peacefully.
"He gave us roads, hospitals, schools. ... He brought us work and there was peace," said Marie Claude, a 41-year-old mother of seven selling grains at a market stall in the Cite Soleil shantytown of the capital.
Preval has a comfortable lead in opinion polls but needs to win at least 50 percent of the votes to avoid a run-off next month. Officials say it will take three days to count the ballots.
Preval's main rivals are Charles Baker, a successful industrialist, and Leslie Manigat, who was president for four months in 1988 before being overthrown in a military coup. There are 33 presidential candidates, but most stand no chance.
U.N. forces used trucks and even mules to ferry ballot papers to voting stations around the country on Monday.
Serious logistic problems forced several postponements and, on the eve of voting, officials warned people in TV ads that some polling stations had been moved.
Many Haitians suspect the unelected interim government has tried to make voting as difficult as possible in poor areas to hurt Preval. Some say they were not told where to cast their ballots and others will have to walk several miles.
U.S. ANTAGONISM
A Preval victory could upset Haiti's business elite and the U.S. government, which in 2004 dropped its earlier support of Aristide and pushed him to step aside.
Security fears forced authorities to postpone the election several times but pro-Aristide gang leaders recently changed tack by backing the elections and telling people to get out and vote.
With that, the level of violence and crime has dropped dramatically in recent days.
Still, experts say Haiti is awash with weapons and that Preval's supporters could turn violent if he loses or if they suspect fraud. On the other side, anti-Aristide armed groups could try to disrupt the election to keep Preval out of power.
Older Haitians remember an election day massacre in 1987, when thugs allegedly linked to the army murdered more than 30 people and authorities quickly scrapped what was supposed to be the first democratic vote after Duvalier's fall.
About 9,000 U.N. peacekeepers are in Haiti and some will stand guard at polling stations in dangerous neighborhoods on Tuesday to prevent a repeat attack on voters.