Maduro's stunningly close victory over Henrique Capriles came after a campaign in which the winner promised to carry on Chavez's self-proclaimed socialist revolution while the challenger's main message was that Chavez's 14-year regime put Venezuela on the road to ruin.

Maduro, acting president since Chavez's death, held a double-digit advantage in opinion polls just two weeks ago, but electoral officials said he got just 50.7 per cent of the votes to 49.1 per cent for Capriles with nearly all ballots counted.