SANTO DOMINGO, Dominican Republic (Reuters) -- Three people were killed and two were wounded in an exchange of gunfire at a polling station on Sunday at the start of a presidential election in the Dominican Republic, local media said.

Witnesses in the town of Barahona, about 110 miles (180 kilometers) southwest of the capital Santo Domingo, said fighting erupted between a handful of rival supporters of the two main candidates at a polling station. At one point the men pulled out pistols and fired at each other.

Opinion polls have shown opposition candidate and ex-president Leonel Fernandez will likely beat incumbent Hipolito Mejia as voters punish the president for a slumping economy in the Caribbean nation of 8.5 million people.

Fernandez, candidate of the centrist Dominican Liberation Party, needs at least 50 percent plus one of the vote to avoid a run-off vote on June 30.

There are several other candidate, but only one, Christian Democrat Eduardo Estrella, has a significant poll showing, with about 10 percent support. The polls are open until 6 p.m. EDT (2200 GMT).

Fernandez, a 50-year-old lawyer and academic who has led Mejia by at least 20 percentage points in opinion polls, was president from 1996-2000 and has promised to restore the country to the prosperity it enjoyed under his watch, when annual economic growth averaged more than seven percent.

Mejia, a 63-year-old agricultural scientist who overrode the initial objections of his ruling Dominican Revolutionary Party to run again, has blamed the crisis on factors beyond his control. The economy began its slide after the September 11, 2001 attacks on the United States and was sent into crisis by the collapse of a leading private bank a year ago.

The Dominican Republic, which is heavily dependent on imports, has seen its peso slide to a third of the value it had against the U.S. dollar in 2000, inflation up to 50 percent, the collapse of small businesses and daylong power cuts. The country went to the International Monetary Fund last year and secured a $600 million dollar loan to tide it through the crisis.

The latest poll, published on Friday by El Diario Libre and conducted by Gallup earlier this month, gave Fernandez 54 percent of the vote and Mejia 30 percent, with a three percent margin of error. That would give Fernandez a good chance of winning the 50 percent plus one vote he would need to win outright on Sunday.

The Dominican Republic shares the island of Hispaniola with Haiti, the poorest country in the Americas, but it has enjoyed relative political and economic stability compared to its neighbor. The recent crisis in Haiti, in which an armed revolt ousted former President Jean-Bertrand Aristide, appeared not to have spilled over as an election issue.

Copyright 2004 Reuters.