Venezuelans lined up for hours in searing tropical heat on Sunday to vote in the biggest electoral test yet to President Hugo Chavez's socialist rule from a young rival tapping into discontent over crime and cronyism.
Henrique Capriles, a centrist state governor, narrowed the gap with Chavez in final polls thanks to a vigorous campaign that generated widespread enthusiasm, giving the opposition its best chance in 14 years to unseat the popular president and take the reins of South America's leading oil exporter.
Chavez has used record oil revenue to support ideological allies around the world while preaching a fiercely anti-American line, so the election is being watched eagerly from the United States and Cuba to Belarus and Iran.
"Today is a day of joy, a day of democracy, a day for the fatherland," Chavez said, adding that a massive turnout meant that voting could take longer than expected.
In a show of vigor, Chavez - who underwent grueling cancer treatment in the past year - shadow-boxed with U.S. actor Danny Glover, who was on hand with some other celebrity fans of the Venezuelan leader to watch him vote.
In poor neighborhoods, where Chavez draws his most fervent following, supporters blew bugles and trumpets in a predawn wake-up call. In the run-down center of Caracas, red-clad loyalists shouted "Long live Chavez!" from the back of trucks.
Despite his remarkable comeback from cancer, Chavez, 58, could not match the energy of past campaigns - or the pace set by his 40-year-old basketball-loving opponent.
Capriles, who showed up to vote in his lucky shoes, struck a conciliatory tone, urging Venezuelans to resolve their differences at the ballot box.
In wealthy enclaves of the capital, Capriles supporters geared up for the vote by banging pots and pans overnight.
In the United States, Venezuelan expats flocked to New Orleans to vote - mostly for Capriles - after Chavez closed the country's consulate in Miami earlier this year.
NO FORMAL ELECTION OBSERVERS
Most well-known pollsters put Chavez in front. But two have Capriles just ahead, and his numbers have crept up in others.
Some worry that violence could break out if the result is contested. There are no formal international observers, but a delegation from the UNASUR group of South American nations is in Venezuela to "accompany" the vote.
Local groups are also monitoring the election and both sides say they trust the electronic, fingerprint voting system. The opposition deployed witnesses to all of the 13,810 polling centers, from tiny Amazon villages to tough Caracas slums.
In a politically polarized country where firearms are common and the murder rate is one of the world's highest, tensions have risen in recent weeks as both campaigns used harsh rhetoric. Three Capriles activists were shot and killed by alleged Chavez loyalists on Sept. 29 at a campaign rally in rural Venezuela.
After voting, Chavez pledged to respect the election results and called on the opposition - who he suggested could cry foul if he comes out on top - to do the same. Some opposition activists fear Chavez could refuse to step down if he loses.
A Capriles victory would unseat the most vocal critic of the United States in Latin America, and could lead to new deals for oil companies in an OPEC nation that pumps about 3 million barrels a day and boasts the world's biggest crude reserves.
OBSTACLES TO ANY TRANSITION
Capriles wants to copy Brazil's model of respect for private enterprise with strong social welfare programs if he is elected - but he would face big challenges from day one. For starters, he would not take office until January 2013, meaning Chavez loyalists could throw obstacles in the way of the transition.
He would also have to develop a plan to tackle high inflation, price distortions and an overvalued currency, while surely butting heads with the National Assembly, judiciary and state oil company PDVSA - all dominated by "Chavistas."
Another big task would be to figure out the real level of state finances. Last month, a Reuters investigation found that half of public investment went into a secretive off-budget fund that is controlled by Chavez and has no oversight by Congress.
If Chavez wins, he would likely consolidate state control over Venezuela's economy and continue backing leftist governments across Latin America such as communist-led Cuba, which receives Venezuelan oil at a discount.
Investors who have made Venezuela's bonds some of the most widely traded emerging market debt are on tenterhooks.
"There is a perception that a tight electoral outcome may trigger social and political unrest and market volatility," Goldman Sachs said in a research note.
Voting runs from 6 a.m. to 6 p.m. (1030-2230 GMT), although polls will stay open later if there are still queues. Results are due any time starting late on Sunday evening.
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