CARACAS // The late socialist leader Hugo Chavez's chosen successor Nicolas Maduro won Venezuela's presidential election by a whisker but now faces opposition protests plus a host of economic and political challenges in the Opec nation.
The 50-year-old former bus driver, whom Chavez named as his preferred heir before dying from cancer, edged out opposition challenger Henrique Capriles with 50.7 per cent of the votes in Sunday's election, according to election board returns. Mr Capriles took 49.1 per cent, a difference of just 235,000 ballots.
Mr Capriles, whose strong showing beat most forecasts, refused to recognise the result and said his team had a list of more than 3,000 irregularities ranging from gunshots to the illegal reopening of polling centres.
"I didn't fight against a candidate today, but against the whole abuse of power," said Mr Capriles, 40, the governor of Miranda state, demanding a recount.
"Mr Maduro, you were the loser ... This system is collapsing, it's like a castle of sand - touch it and it falls."
A protracted election dispute could cause instability in a deeply polarised nation with the world's largest oil reserves.
Though some opposition supporters chanted "fraud", banged pots and pans and burnt tires in protest, Mr Capriles did not call them onto the streets en masse.
Mr Maduro said he would accept a full recount, even as he insisted his victory was clean and dedicated it to Chavez.
"We've had a fair, legal and constitutional triumph," Mr Maduro told his victory rally. "To those who didn't vote for us, I call for unity. We are going to work together for the security and economy of this country."
The election board said Mr Maduro's win was "irreversible" and gave no indication of when it might carry out an audit.
Mr Maduro's slim victory provides an inauspicious start for the "Chavismo" movement's transition to a post-Chavez era, and raises the possibility that he could face challenges from rivals within the disparate leftist coalition.
His supporters set off fireworks, and some sang and danced in the streets, but celebrations were far more muted than after Chavez's comfortable re-election last October.
Some supporters seemed to pay little attention to his speech, and it was only when he played a recording of the late president singing the national anthem that they burst into life.
Mr Maduro's narrow win came as a shock to many ardent Chavez loyalists, who had become accustomed to his double-digit election victories during his 14 years in power, including an 11 percentage point win over Mr Capriles last October.
Mr Maduro's campaign was built almost entirely on his close ties to the late leader and emotional anecdotes about Chavez's final days before succumbing to cancer.
The narrow win leaves him with less authority to lead the broad ruling alliance that includes military officers, oil executives and armed slum leaders. It had been held together mainly by Chavez's iron grip and mesmerising personality.
"This is the most delicate moment in the history of 'Chavismo' since 2002," said Javier Corrales, a US political scientist and Venezuela expert at Amherst College, referring to a brief coup against Chavez 11 years ago.
"With these results, the opposition might not concede easily, and Maduro will have a hard time demonstrating to the top leadership of Chavismo that he is a formidable leader."
It will also add to the difficulty Mr Maduro faces in moving from campaign mode to actually governing a nation with high inflation, a slowing economy, Byzantine currency controls and one of the world's worst violent crime rates.
Blow-out state spending ahead of Chavez's re-election helped spur economic growth of 5.6 per cent in 2012. This year, many private economists expect growth of 2 per cent or less.
In a research note, Barclays said the high level of uncertainty about the short-term political situation was likely to be received negatively by the market. There were few signs, however, that the situation could force Venezuela to default on its debt.
The evaporation of Maduro's big lead in the opinion polls from just last month did prompt some high level soul-searching.
"These results require deep self-criticism," said Diosdado Cabello, the powerful head of the National Assembly whom many Venezuelans see as a potential rival to Mr Maduro. "It's contradictory that some among the poor vote for those who always exploit them."