Jamaica's leading opposition People's National Party has won a landslide election in a vote driven by concerns about crime, corruption and poverty on the picturesque Caribbean island.

Preliminary results late Thursday indicated the left-leaning party had won 41 out of 63 constituencies, giving it a resounding majority and showing the door to Andrew Holness, 39, the country's youngest-ever prime minister.

Within hours of polls closing, local media had called the PNP's victory, and PNP leader Portia Simpson Miller, the designated prime minister, delivered an acceptance speech vowing greater transparency.

"You will know everything. We will never hide anything from you. Now you have a government you can trust," she told jubilant supporters.

Miller, who became the first female prime minister in 2006 but narrowly lost a reelection bid the next year, promised a "partnership with you, the Jamaican people, a partnership with the private sector, the media and civil society."

She said Holness -- of the center-right Jamaica Labor Party (JLP) -- had called earlier to concede defeat and offer his congratulations, describing his mood as "gracious."

In an interview carried live on national radio and television, Holness said his party would start campaigning for the next election -- due in five years -- "tomorrow morning."

Turnout was high in the palm-fringed former British colony of three million -- the birthplace of reggae icon Bob Marley -- where voters' chief concerns were crime, corruption and unemployment.

Monitors reported long lines of voters in some districts, mainly due to technical problems with the voting machines, but Thursday's elections did not see the violence that had marred previous votes.

"We have had reports from some supervisors who say things are going smoothly while there are others who say the machines are slow. But slow is relative because some persons just don't want to wait," Director of Elections Orette Fisher was quoted as saying in the Jamaica Observer.

Over 1.6 million voters -- 75 percent of registered voters -- were projected to have cast their ballots by the time polls closed at 5:00 pm (2200 GMT). The 2007 vote saw a lower turnout, at 60 percent.

Police reported a shooting in the country's southeast, but officials did not believe it was politically motivated.

Residents provided their own security at the polls in the PNP stronghold of Trench Town, a local gang member said. There, voters flooded polling stations dressed in orange T-shirts -- the color of the opposition party -- and shops were closed for two hours to allow employees to vote.

Surveys conducted by pollster Don Anderson -- who has correctly called the last three elections here -- showed the opposition PNP marginally ahead up to late last week, but most pundits had said the race was too close to call.

Holness assumed office on October 23 when Bruce Golding stepped down under pressure.

Golding, who led the JLP to victory in 2007 and ended 17 straight years of PNP rule, resigned in the political fallout from the government's fight against the extradition to the United States of Christopher "Dudus" Coke, reportedly the former leader of the Shower Posse, a JLP-tied gang.

Coke -- accused of running a vast arms and drug trafficking operation -- pleaded guilty in August to one count of racketeering conspiracy.

He was arrested a month after a massive May 2010 assault on a Kingston slum that left more than 70 dead and divided the island nation.

Many slum-dwellers had hailed him as a Robin Hood figure who provided security and small-time jobs, but the gang's link to the JLP has hurt its sway over poor areas still traumatized by the violence.

"My grandfather voted JLP, my father voted JLP, and I have always voted JLP, but I lost three children in May 2010, so for me now it's PNP or nothing," a slum resident told AFP on condition of anonymity.

When campaigning officially ended at midnight Tuesday, gunfire rang out at a JLP event in Westmoreland. One party supporter was killed and two others were wounded, authorities said. Both candidates condemned the violence.

While police have cited figures showing a decline in violent crimes, voters remain deeply concerned over street crime, as well as jobs and corruption in the public sector.