Voters in Venezuela are set to go to the polls in what is predicted to be the country's most tightly contested presidential election in a decade.
Left-wing incumbent Hugo Chavez, first elected in 1999, is being challenged by opposition leader Henrique Capriles.
Mr Chavez wants to continue what he calls his socialist revolution while Mr Capriles has promised to restore economic growth.
The incumbent is seeking a fourth term in office, and it comes after he was diagnosed with cancer last year, although he says he has now fully recovered.
A colourful and often controversial figure on the international stage, Mr Chavez, 58, has nationalised key sectors of the economy, the BBC reports.
Venezuela is a major oil producer and high oil prices over the past decade have allowed his government to fund health-care, education programmes and social housing.
However, Mr Capriles, 40, and the opposition say the president's policies have led to bureaucracy, inefficiency, and shortages. They also accuse Mr Chavez of authoritarianism and of suppressing the judiciary and silencing critics in the media.
Mr Capriles says a lack of investment in Venezuela's crucial oil industry has led to a decline in production.
Almost 140,000 soldiers will be deployed to guard more than 10,000 voting centres. Almost 19 million Venezuelans are eligible to vote in the election.
A week before the election, three opposition activists were killed during a campaign rally, and four people were injured in a shooting during a voting rehearsal in September.