Volodymyr Zelenskiy, 41, who is appealing to voters fed up with entrenched corruption, has consistently led opinion polls in a three-horse race against incumbent President Petro Poroshenko and former Prime Minister Yulia Tymoshenko
Ukrainians will cast their ballots in a presidential election on Sunday in which a comedian with no political experience and who plays a fictional president in a popular TV series is tipped to win the first round.
Volodymyr Zelenskiy, 41, who is appealing to voters fed up with entrenched corruption, has consistently led opinion polls in a three-horse race against incumbent President Petro Poroshenko and former Prime Minister Yulia Tymoshenko.
At stake is the leadership of a country on the front line of the West's standoff with Russia after the 2014 Maidan street protests ejected Poroshenko's Kremlin-friendly predecessor and Russia annexed the Crimean peninsula.
Investors are watching to see if the next president will push reforms required to keep the country in an International Monetary Fund bailout programme that has supported Ukraine through war, sharp recession and a currency plunge.
No candidate is expected to receive more than half the votes, meaning the election would go to a run-off on April 21. Out of a crowded field of 39 candidates, none of the likely winners wants to move Ukraine back into Russia's orbit.
Poroshenko has fought to integrate the country with the European Union and NATO, while strengthening the military which is fighting Kremlin-backed separatists in the east of the country.
Pushing the use of the Ukrainian language and instrumental in establishing a new independent Orthodox church, the 53-year-old confectionary magnate casts himself as the man to prevent Ukraine again becoming a Russian vassal state.
But reforms crucial to keep foreign aid flowing have been patchy. Conflict in the eastern Donbass region has killed 13,000 people in five years and rumbles on despite Poroshenko's promise to end it within weeks. Frustration over low living standards and pervasive corruption has left the door open for Zelenskiy.
Just 9 per cent of Ukrainians have confidence in their national government, the lowest of any electorate in the world, a Gallup poll published in March showed.
Zelenskiy has tapped into the anti-establishment mood, though his inexperience makes Western officials and foreign investors wary and sceptics question his fitness to be a wartime commander-in-chief.
Inviting comparisons with U.S. President Donald Trump and Italy's Five-Star movement, his campaign has relied heavily on social media and comedy gigs of jokes, sketches and song-and-dance routines that poke fun at his political rivals.
"He embodies the perceived need for 'new faces' in politics and could sway the young, pro-reform electorate to his side," said Economist Intelligence Unit analyst Agnese Ortolani.
Zelenskiy's campaign has blurred the line between reality and the TV series in which he plays a scrupulously honest history teacher who accidentally becomes president.
In series three, which began airing in March, his character is flung into prison and the country falls under the control of oligarchs, populists and ultranationalists, and eventually gets broken up into 28 states. Thinly-disguised characters resembling Poroshenko and Tymoshenko come to power.
The election has been marred by allegations of fraud and vote-buying, meaning one or more of the candidates could contest the result. Ultranationalists acting as election observers have also caused concern about the prospect of violence.
Accused of cheating by Tymoshenko, Poroshenko attended a public prayer on the banks of the Dnieper river in Kiev on Saturday to pray for the elections to be free and fair and, in his words, for "the wisdom of the people who tomorrow will determine the future of Ukraine."