Results from Georgia's presidential runoff showed the ruling party-backed candidate, who favours balancing the ex-Soviet republic's relations with Moscow and the West, defeating her rival who advocates a stronger pro-Western line.
Georgia's ruling party candidate Salome Zurabishvili was on the verge of winning a hotly contested presidential vote, nearly complete results showed Thursday, as the opposition called for protests over alleged fraud.
Former French diplomat Zurabishvili was on 59.61 percent of the vote after Wednesday's second round, the central election commission said, following completed counts from 98.41 percent of polling stations.
Her rival Grigol Vashadze, from an alliance of 11 opposition parties led by exiled ex-president Mikheil Saakashvili's United National Movement (UNM), had 40.3 9 percent of the vote, the commission said.
Western powers are closely watching the vote, seen as a test for the democratic credentials of the Caucasus nation as it seeks EU and NATO membership.
Although the new head of state will have a largely ceremonial role, the vote is considered a trial run for the contest between Ivanishvili's party and the opposition in more important parliamentary polls set for 2020.
Turnout was 56.23 percent when the presidential polls closed at 8:00 pm (1600 GMT) on Wednesday.
Earlier, an exit poll by US firm Edison Research suggested that Zurabishvili, who is backed by billionaire tycoon Bidzina Ivanishvili's Georgian Dream party, had won 55 percent of the vote against 45 percent for Vashadze.
After the exit poll results were announced, Saakashvili immediately claimed "mass electoral fraud", in a statement to the pro-opposition Rustavi-2 television channel.
"The oligarch has stamped out Georgian democracy and the institutions of elections," he said, referring to Ivanishvili.
"I urge Georgians to defend our freedom, democracy and the law. I call on you to start mass peaceful rallies and demand snap parliamentary polls."
Tensions increased ahead of the second round as the opposition accused the government of voter intimidation and claimed that ruling party activists had attacked members of Vashadze's campaign staff.
Zurabishvili in turn said she and her children had received death threats through text and voice messages from people affiliated with the UNM.
Rights groups have also accused government officials of vote-buying on a "widespread" and "unprecedented" scale, an allegation rejected by Georgian Dream party leadership.
The Georgian Prosecutor General's office said it launched an investigation into the allegations.
Daughter of refugees
Zurabishvili, a 66-year-old independent lawmaker, is the daughter of refugees who fled Georgia in 1921 for Paris after the country's annexation by the Red Army.
Her career in France's foreign service culminated in a posting to Tbilisi, where then-president Saakashvili appointed her foreign minister.
But Zurabishvili quickly made enemies among the parliamentary majority, with MPs and some senior diplomats accusing her of arrogance and impulsiveness.
When she was sacked after a year in the job, thousands took to the streets of the capital to protest her dismissal.
"The outcome of the vote will determine not only who won the election, but also mark either progress or (a) setback for Georgia's young democracy," political analyst Gela Vasadze said.
Both candidates have promised to lead Georgia closer to the West, but analysts say they have different approaches to pursuing that goal.
"Their records as ex-foreign ministers show that Vashadze is more closely associated with Washington, while ... Zurabishvili is clearly more EU-orientated," Vasadze said.
Vashadze's election would also likely irritate Russia, which fought a bitter war with Georgia during the presidency of his ally Saakashvili.
"For the Kremlin, a UNM candidate's win is like a red rag to a bull and may lead to increased tensions between the two countries," said analyst Gia Nodia.
Vashadze, a 60-year-old career diplomat, has criticised Ivanishvili's "informal oligarch rule" amid growing discontent over the government's failure to tackle poverty.
Ivanishvili, Georgia's richest man, stepped down as premier in 2013 after a year in office but is still seen as the country's de facto ruler.
The vote is Georgia's last direct leadership poll as it transitions to a parliamentary form of governance.
The first round on October 28 saw Zurabishvili take 39 percent of the vote, against 38 for Vashadze.
More than 3.5 million people were eligible to vote in the election monitored by international observers from the Organisation for Security and Cooperation in Europe.