Feb 15 Venezuelans voted on Sunday in a referendum on scrapping term limits and allowing socialist President Hugo Chavez to stay in power for as long as he keeps winning elections.
The self-styled revolutionary this month celebrated a decade at the helm and says he needs another 10 years to continue his anti-poverty campaigns. Opposition leaders call him a fledgling tyrant who wants to stay in office for life.
Polls show Chavez, who should leave office in 2013 if he loses, with a slim lead.
The following are scenarios for Sunday's vote:
A victory in the referendum would strengthen Chavez's mandate and give him greater confidence to expand his drive toward Cuban-inspired socialism that has included nationalizations and increased state control over the economy.
He is likely to interpret a clear victory as a license to push forward with policies such as strengthening state-backed community councils that could supplant opposition politicians and advancing land redistribution reforms.
Winning the vote would give him leeway to take unpopular economic measures such as spending cuts or new taxes. The OPEC nation faces declining oil income and slower growth amid the global financial crisis.
It may also bolster him to be more combative as the economy worsens, meaning the government could be given a freer hand to take over businesses that become too insolvent to pay their workers or refuse to abide by government price controls. Chavez launched a wave of aggressive nationalizations after his last election vote victory in 2006.
A loss on Sunday would embolden opponents with a second clear victory against Chavez after shooting down a 2007 constitutional reform package that included the current amendment.
Opposition leaders, who also gained ground in local elections last year, could request a recall referendum against him in 2010.
A weakened Chavez could respond by hunkering down to weather the economic crisis and slow his reforms as he did in early 2008 after his constitutional overhaul was rejected.
However, a defeat could also make Chavez more combative. He frequently relies on confrontation and divisive rhetoric to rally supporters in the face of adversity.
He could effectively repeat Sunday's vote by calling yet another referendum or even call a body, known as a constituent assembly, to rewrite the constitution in his favor. He has not ruled out such moves. But defeat would make it more difficult to control his unwieldy coalition of political allies. Cabinet members with their own ambitions could prepare to stand in the 2012 presidential vote.
A very close race hinging on only one or two percentage points could spark a prolonged vote count and opposition protests, possibly affecting the country's debt prices as investors fret over uncertainty.
Few opposition leaders will immediately cry fraud as they did after Chavez beat out a 2004 recall referendum. But they may accuse him of seeking to rig the results if the count drags on.
Even a slim Chavez loss would be a major step forward for opponents as it would further erode the impression among many voters that the president is unbeatable at the ballot box.
A small win for Chavez, who for years had won elections by wide margins, would demonstrate electoral weakness and give him less of a mandate in a tough year. (Reporting by Brian Ellsworth, Editing by Saul Hudson and Kieran Murray)
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