* Medina declares victory as results show huge margin of win
* Slow pace of vote count exacerbates deaths and violence
* Voters unwilling to ditch surging GDP growth, social projects (Adds latest results)
By Jorge Pineda
SANTO DOMINGO, May 16 (Reuters) - President Danilo Medina declared electoral victory in the Dominican Republic on Monday as results showed him ahead with a huge margin, but the win was marred by deaths and violence exacerbated by the slow pace of the vote count.
Medina swayed voters with a record of surging GDP growth and social projects that outweighed stubborn poverty, high crime and accusations of graft in the Caribbean's largest economy.
"We have received the support of the majority of the Dominican people," Medina said in a speech at his campaign headquarters, thanking the nation for his victory.
Final results were still not out more than 24 hours after polls closed on Sunday night, a situation electoral authorities blamed for tension between candidates that led to six deaths and unrest in the provinces.
Television in the eastern city of Higuey reported gunfire on Monday afternoon and said torched tires were still burning at night.
In its latest bulletin, the electoral board said that with votes counted at 67 percent of polling stations, Medina had won 62 percent of the vote, exceeding the 35 percent of his closest rival, Luis Abinader.
Abinader has yet to concede defeat and said he would make his first comments after the election on Tuesday.
The margin is large enough to avoid a runoff, a first for Latin America's fastest growing economy, whose luxury beach resorts and golf courses make it the Caribbean's most visited destination.
The weak showing by Abinader, a businessman, was a sign Dominicans were unwilling to ditch the president's record of 7 percent GDP growth in 2014 and 2015 for untested promises of more social spending and lower crime.
School building and health spending has helped cut poverty, which rose to 41 percent in the first year of Medina's term but has fallen sharply in the past two years, the World Bank says.
The remaining six candidates combined had about 3 percent of votes, including the first two women running for the presidency in a Dominican election.
After Medina's victory speech, celebrations broke out in the capital, with cavalcades of supporters blaring reggaeton music.
A left-of-center economist, Medina has enjoyed high popularity during much of his first four-year term in the country of 10.4 million. Electoral rules were changed to allow him to run for a second consecutive term.
Medina's Dominican Liberation Party has been continuously in power since 2004, which critics say has led to corruption.
Abinader's campaign called for change and focused on graft allegations over a power plant awarded to Brazilian engineering conglomerate Grupo Odebrecht.
Medina's campaign chief, João Santana, returned to Brazil in February to face charges Odebrecht paid him funds siphoned from Brazil's state oil company, Petrobras, to finance the 2014 poll campaign of suspended Brazilian President Dilma Rousseff.
Medina has not referred to the Petrobras scandal, but admitted the Brazilian was his top adviser. Santana has called the allegations "baseless."
The Dominican Republic has about eight times the GDP of Haiti, its poor neighbor on the island of Hispaniola.
Haiti has missed several deadlines to hold its own presidential election and saw a flare-up of violence on Monday. (Editing by Frank Jack Daniel and Clarence Fernandez)