Billionaire Georgia opposition leader says vote win hours away TBILISI (Reuters) - The billionaire leader of the opposition in Georgia on Saturday told tens of thousands of his supporters that the current government loyal to President Mikheil Saakashvili had only hours left in power before it was voted out in an election on Monday. Addressing crowds in a central square in the capital Tbilisi after days of protests against prison brutality, Bidzina Ivanishvili was making his final pitch before the vote which his six-party "Georgian Dream" coalition hopes to win. This regime cannot be the leadership of our country ... This system should collapse ... We have won already, but it should be officially confirmed on October 1," he said. "This regime's hours are numbered," said the once-reclusive tycoon, whose wealth at $6.4 billion equals nearly half of Georgia's economic output. According to Saakashvili's supporters the election in the country of 4.5 million - an important transit route for oil and gas to the West - may determine whether Georgia moves closer to Russia or remains a staunch U.S. ally. They accuse Ivanishvili, who made much of his money in Russia, of being a Kremlin stooge, a charge he denies. A prison abuse scandal has increased tensions ahead of the vote, prompting calls for restraint from the West. Nationwide protests broke out last week after two local television channels broadcast images of prison guards beating and raping inmates. The two channels are seen as hostile to Saakashvili and one is owned by Ivanishvili. Saakashvili, 44, became a political darling in the West when he rose to power in 2004 after a bloodless revolution that toppled Eduard Shevardnadze, a former Soviet foreign minister. But opponents have since accused him of monopolizing power and criticized him for leading Georgia into a disastrous five-day war with Russia in 2008 which saw his country lose one fifth of its territory. Saakashvili's promise to take Georgia into the NATO military alliance remains unfulfilled but his oft-repeated desire to do so has soured relations with Russia, one of the small country's most important trading partners. Saakashvili has promised to leave the presidency next year but needs his party to win in Monday's parliamentary election in order to retain influence and avoid the risk of political oblivion. An independent opinion poll in August put Ivanishvili's "Georgian Dream" coalition a long way behind Saakashvili's United National Movement ahead of the October 1 election, but showed that 43 percent of respondents could vote either way. Analysts believe support for the opposition has risen since last week's protests against prison brutality and that Ivanishvili and his movement pose a real threat to Saakashvili's government. The 2008 war with Russia put Abkhazia and the rebel region of South Ossetia, both now recognized by Moscow as independent nations, further from Georgia's reach and Russian leaders depict Saakashvili as a hothead itching to take the regions by force. For his part, Saakashvili says President Vladimir Putin wants to gain sway over a country that was under Russian or Soviet control for almost two centuries. He has called the prison scandal "Russian mud" financed with "Russian money." The heads of the parliamentary delegations of the Organisation for Security and Cooperation in Europe (OSCE), the Council of Europe, NATO and the European Parliament on Saturday called on all political parties and leaders to exercise restraint and to renounce violence. "We believe that the Georgian people must be able to exercise their civil and democratic rights and choose their representatives in a peaceful atmosphere," European diplomats said in a joint statement. Political leaders should be chosen through the ballot box and not on the streets. Addressing his supporters in several towns in western Georgia on Saturday, Saakashvili said the country would conduct "exemplary elections." The last time Georgia held a parliamentary election - in 2008 - OSCE observers said the poll was an improvement on a presidential vote earlier that year but was still marred by a number of flaws. Hit by the war with Russia and the global financial crisis, Georgia's economy has been growing again since 2010. Editing by Andrew Osborn