BISHKEK (Reuters) - Kyrgyzstan votes on Sunday in a presidential election with no candidate expected to win outright and observers predicting a close runoff between two pro-Russian candidates, one of whom is backed by the outgoing leader.
The mainly Muslim nation of 6 million people is already a close ally of Moscow and hosts a Russian military base, helping its former Soviet overlord project power across the region where China and the United States also vie for influence.
In contrast to its Central Asian neighbors, mostly run by autocrats, Kyrgyzstan is a boisterous democracy that produces sometimes chaotic changes of leadership.
After its first two presidents after the Soviet Union's demise were ousted by violent riots, the country restyled itself as a parliamentary republic where presidential powers are mostly limited to foreign policy and security matters.
But outgoing president Almazbek Atambayev strengthened executive powers last year by calling a referendum on constitutional changes.
Also, alliances between parliamentary factions have been fluid, meaning a new leader could easily build a coalition around himself.
Constitutionally barred from seeking a second six-year term, Atambayev is backing an ally, former prime minister and experienced bureaucrat Sooronbai Jeenbekov, 58, whose victory would allow the outgoing leader to remain a powerful figure.
Atambayev and Jeenbekov's Social Democratic party has the biggest faction in parliament and dominates the coalition cabinet.
But they face stiff opposition from oil tycoon Omurbek Babanov, 47, whose Respublika-Ata Zhurt (Fatherland) party has the second-biggest parliamentary faction and whose poll numbers suggest he and Jeenbekov will compete in a tight runoff.
Babanov, also a former prime minister, has accused the government of abusing its powers to ensure Jeenbekov's victory after the authorities accused some of his campaign supporters of plotting a coup and planning to bribe voters.
Babanov has denied any wrongdoing and dismissed the charges against his supporters as dirty election tactics.
Atambayev and his cabinet have also accused Kazakhstan, a bigger and wealthier neighbor, of backing Babanov - which both Babanov and the Kazakh government deny.
Despite their differences, both Jeenbekov and Babanov have said they considered Russia - where hundreds of thousands of Kyrgyz migrant laborers work - a strategic partner.
Polls close at 8 p.m. local time (1400 GMT) and preliminary results may be published a few hours later. There is no set date for a second round, which takes place in the event that none of the 13 candidates wins over 50 percent of the vote.
(Reporting by Olga Dzyubenko; Writing by Olzhas Auyezov; Editing by Ros Russell)