TBILISI: Georgia votes in a presidential election Sunday to choose a successor to flamboyant reformer Mikheil Saakashvili, with a loyalist of his billionaire rival Prime Minister Bidzina Ivanishvili favourite to claim victory in the ex-Soviet state.
The poll marks the end of US-ally Saakashvili's legally permitted two terms in power and his rancorous year-long political cohabitation with nemesis Ivanishvili, who has also pledged to step down shortly after the vote.
The election in the tiny Western-backed republic -- which under Saakashvili fought a brief 2008 war with Russia over separatist region South Ossetia -- will then see constitutional changes shift a raft of key powers from the next president to the prime minister.
"These elections are important and they will usher in a new chapter," George Mchedlishvili, a Caucasus expert at London-based Chatham house, told AFP.
"It will be the first time in the history of Georgia when the country will not be associated with the president alone."
Opinion polls before the vote have put Giorgi Margvelashvili -- a little-known former education minister representing Ivanishvili's Georgian Dream coalition -- well ahead of ex-parliament speaker David Bakradze from Saakashvili's United National Movement (UNM).
Pro-western Margvelashvili has said he is so sure of securing the 50 percent needed to win the first round -- which sees 23 candidates competing -- that he will withdraw his candidacy if the vote goes to a run-off.
But an aggressive challenge from former parliament chairwoman Nino Burjanadze -- along with a sizeable chunk of undecided voters -- could push the election to an uncertain second round.
OSCE observers have described the campaign as "notably calmer" than fraught parliamentary elections last year that saw Ivanishvili wrest power away from Saakashvili's party in Georgia's first smooth transition of power.
"This election has a relatively low stake -- whatever the result Georgian Dream will continue to run the government," said Koba Turmanidze, Georgia country director at the Caucasus Research Resource Centre.
But while his coalition will stay in power, Ivanishvili, whose express aim was to dislodge Saakashvili, has pledged to name a successor as premier and step down shortly after the poll.
Whoever is in charge, the government insists it will seek to join NATO and the European Union, a top Saakashvili ambition that enraged northern neighbour Russia.
In 2008 those tensions exploded into a disastrous five-day war with Russia that saw Georgia effectively lose two Kremlin-backed breakaway regions, where Moscow has now stationed thousands of troops.
Despite attempts by Ivanishvili's coalition over the past year to improve ties with Russia -- which have met with limited success -- few expect them to change Georgia's pro-Western course.
"The fundamentals of Georgia's foreign policy are not likely to change," said Alex Nice, a Caucasus analyst with the London-based Economist Intelligence Unit.
While the election campaign may have been calm, Western allies have expressed concern over perceived selective justice that has seen a string of Saakashvili's close allies arrested since his party lost power.
Ivanishvili, who denies that there is a political witch-hunt, has dismissed Saakashvili as a "political corpse" and warned that he could face prosecution once his immunity ends when he leaves office.
Saakashvili has pledged to remain active in politics and said he would not be "caged like a zebra," an apparent dig at Ivanishvili who keeps the exotic animals at his country estate.
Since independence from the Soviet Union, the mountainous Caucasus nation of some 4.5 million people has gone through economic collapse, civil war and radical reform.
During a tumultuous decade under Saakashvili -- who came to power after ousting Eduard Shevardnadze in the 2003 "Rose Revolution" -- Georgia cut corruption, built new infrastructure and revived the country's devastated economy.
The capital Tbilisi -- once mafia-ridden and starved of electricity -- is now studded with glittering government buildings and Western-style supermarkets but much of the country still remains mired in poverty.
Saakashvili's reforms angered many who felt left out by the rush to change and took to the streets to protest his policies.
Riot police brutally broke up those rallies, a move that disturbed Western backers, who saw Saakashvili as a pioneering ex-Soviet democrat.
Polls open Sunday at 0400 GMT and close at 1600 GMT, with results expected shortly afterwards. Some 3.5 million voters are called to the polls.