Opinion polls say the frontrunner is a former paratroop colonel, Hugo Chavez, who was jailed for two years for a failed coup attempt in 1992.

Mr Chavez embraces his daughter

His Patriotic Pole coalition won control of Congress in November, and he has promised to sweep away the rampant corruption that characterised previous Venezuelan administrations.

Mr Chavez's populist rhetoric has brought him support with the masses, but his authoritarian background and calls for a slowing of privatisation and free-market economic reforms has provoked fears within Venezuela's business establishment.

For the first time in the country's 40-year democratic history, neither of the two main centrist parties that have traditionally dominated Venezuelan politics have put forward a candidate.

In an attempt to thwart Mr Chavez, both the centre-left Democratic Action Party and the centre-right Copei Party have thrown their support behind an independent candidate, Henrique Salas Romer.

American educated: Henrique Salas main opponent

Mr Romer is an American-educated businessman who built a reputation for efficiency during his time as governor of the industrial state of Carabobo.

In a bitter showdown the two have accused each other of being corrupt, dictatorial and of being Satan himself. They have also made sweeping promises to boost Venezuelans' standard of living and improve health, education and housing.

Yet they have said very little about their proposals to tackle the country's grim economic situation.

Economic challenge

In the last 10 years, the global slump in oil prices has badly affected the economy of the oil-rich country and living standards have taken a battering.

The country has now sunk into a full-blown recession, with negative economic growth and rising unemployment. In addition to persistent inflation and soaring interest rates, the incoming government faces a budget deficit as high as 8% of GDP.

Economists say the country's next president will have no choice but to ask for loans from international creditors and swallow the bitter economic measures they prescribe.