Georgia's opposition on Tuesday scented victory over President Mikheil Saakashvili's ruling party in hard-fought parliamentary polls, but a complex voting system means the result could go down to the wire.
Supporters of billionaire Bidzina Ivanishvili's Georgian Dream opposition coalition celebrated into the night after exit polls offered them hope of a dramatic victory in Monday's vote but the ruling party warned it could still win, sparking fears of potential unrest.
The tense showdown between Saakashvili's long-dominant party and Ivanishvili's recently created coalition turned increasingly bitter after a prison torture scandal prompted nationwide protests in the Western-backed ex-Soviet state.
Ivanishvili declared victory immediately after exit polls for several Georgian television channels suggested Monday that his coalition was either ahead or running neck-and-neck with the ruling party in the proportional-vote section of the contest.
"We have won! The Georgian people have won!" Ivanishvili said in a speech televised by opposition channel TV9.
But his coalition could still lose because almost half of parliamentary seats are decided on a first-past-the-post basis rather than the proportional representation system that provided the basis for the exit polls.
"We need to wait for results, but it seems clear that the Georgian Dream coalition has won the majority in the proportional vote but in single-mandate constituencies, the majority of votes has been secured by Georgia's (ruling) United National Movement," Saakashvili said in televised comments.
His party's spokeswoman Chiora Taktakishvili was more explicit: "The United National Movement will have a solid majority in the new parliament," she said in a televised statement.
Turnout was 61 percent, the Central Election Commission said.
"The elections were held in an unprecedentedly competitive environment and the final result will accurately reflect the people’s will," the commission's chief Zurab Kharatishvili said in a statement.
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Cars full of more euphoric supporters raced up and down the capital's main street, sounding their horns, whistling and waving flags.
"I was not expecting this. I'm sure everything will change for the best," one woman in the noisy crowd, Maya Asanidze, told AFP.
Before the torture scandal sparked by revelations of the brutal beating and rape of male prison inmates erupted last month, most opinion polls gave the ruling party a significant lead, but the outrage seriously damaged its campaign.
Ivanishvili, who made his fortune through privatisation deals in Russia, threatened to call mass demonstrations should Western observers fail to declare the vote fair.
In a controversial move that troubled the West, the tycoon was stripped of his Georgian citizenship after announcing last year that he would challenge Saakashvili, and is currently a French citizen.
He symbolically did not vote on Monday despite constitutional amendments earlier this year that allowed him to do so.
The highly-polarised campaign in the small Caucasus republic of 4.5 million people was described by international OSCE election monitors as "confrontational and rough".
Georgia's main backers, the United States and European Union, called for a fair vote and emphasised that democratic progress was crucial for the Caucasus state's ambitions to join Western institutions such as NATO.
The polls were a "litmus test of the way democracy works in Georgia", NATO Secretary-General Anders Fogh Rasmussen said Monday.
Saakashvili's party controlled 119 of the 150 seats in the outgoing parliament and has dominated Georgia since the charismatic lawyer rose to power after the 2003 "Rose Revolution" that ousted the country's former leader, the wily ex-Soviet foreign minister Eduard Shevardnadze.
The elections are crucial for Georgia's future because its parliament and prime minister will become stronger and the presidency's powers will dwindle under constitutional changes that come into force after Saakashvili's two-term rule ends in 2013.
Since post-Soviet independence, Georgia has gone through economic collapse, civil war and repeated outbreaks of political unrest that have seen two presidents deposed, as well as a five-day war with arch-foe Russia in 2008.
The first official results are awaited early Tuesday.