(Reuters) - Georgia elects a new president on Sunday in a vote that will end Mikheil Saakashvili's decade-long rule and test confidence in the ruling Georgian Dream coalition led by billionaire prime minister Bidzina Ivanishvili.
Twenty-three candidates will run in the election, the largest number since the former Soviet republic held its first presidential election in 1991. Saakashvili is barred from running after serving two terms.
Here are some facts on the main candidates and the rules.
GEORGY MARGVELASHVILI, 44, Georgian Dream's presidential candidate, is the front runner, according to opinion polls.
Ivanishvili, who describes Margvelashvili as his close confidant, has predicted a first-round victory, adding that his candidate should pull out if the vote goes to a second round.
Margvelashvili, who holds a doctoral degree in philosophy from Tbilisi State University, was a rector of the Georgian Institute of Public Affairs. Ivanishvili appointed him as education minister after last year's parliamentary election, and later promoted him to deputy prime minister.
DAVID BAKRADZE, 41, was nominated by Saakashvili's United National Movement (UNM) Party and leads its group in parliament, where he was speaker from 2008 to 2012.
Bakradze, a mathematician who according to recent polls enjoys the highest favourability rating among opposition politicians, has accused the Georgian Dream government of failing to deliver on its economic and social promises.
NINO BURJANADZE, 49, was one of the leaders of Georgia's 2003 "Rose Revolution". When Saakashvili was elected president, she became speaker of parliament but resigned in early 2008, criticising the president's record on democracy, and formed her own opposition party.
A lawyer who lists former British Prime Minister Margaret Thatcher among her idols, Burjanadze served as an interim president twice, for 40 days each time. She led street protests that came to a violent end in May 2011, when riot police broke up a demonstration on the capital's Rustaveli Avenue.
Burjanadze accuses the government of betraying its election promise to restore justice, and criticises it for failing to re-engage fully with Russia.
ELECTORATE: The Central Election Commission (CEC) says there are about 3.5 million eligible voters in the Caucasus nation of 4.5 million.
VOTING HOURS: Polls open at 8 a.m. (0400 GMT) and close at 8 p.m. (1600 GMT). First official preliminary results are expected within hours of polls closing.
RULES: Georgian presidents are elected every five years. The presidency is limited to a maximum of two terms.
There is no turnout threshold for an election to be valid.
A candidate must get at least 50 percent plus one vote to be elected outright in the first round.
A run-off is held within two weeks if none of the candidates wins a simple majority in the first round.
Reporting by Margarita Antidze; Editing by Elizabeth Piper and Mark Trevelyan