A Ukrainian policeman stands in front of a voting booth as he secures the polling station in the village of Kosmach in the Ivano-Frankivsk Oblast (province), western Ukraine May 24, 2014. (Kacper Pempel/Reuters)

As Ukraine heads to the polls Sunday, one man is a strong favorite to win: candy tycoon Petro Poroshenko, who has vaulted to the top of his nation’s political scene on the hope that he can unite a deeply divided electorate.

Ukraine was already suffering from economic troubles when pro-Western street protests forced Kremlin-friendly President Viktor Yanukovych to flee the country Feb. 22. Soon thereafter, Russian ­forces ­seized the Crimean Peninsula. And as an insurgency has grown in Ukraine’s east, the question ahead of the election was less about the eventual winner and more about what challenges the new president will face in the coming months.

Opinion polls released in recent days show that the businessman has a shot at capturing more than 50 percent of the vote in a crowded field of 20 candidates, avoiding a June 15 runoff. But even in a runoff, his main challenger, Yulia Tymoshenko, lags behind him in most polls.

Poroshenko, 48, a former foreign and economics minister, is a savvy veteran of Ukraine’s political scene, adept at working with both pro-Russian and pro-Western leaders. Once an ally of Yanukovych, he was the first member of Ukraine’s powerful oligarchs to cast his lot with the pro-Western protesters who took to Kiev’s main square, the Maidan, in November to demand more political freedoms and that the country align itself with the European Union.

At an early stage of the protests, Poroshenko, who Forbes estimates is worth $1.6 billion, tried to play conciliator, using a bull­horn to negotiate with an angry crowd as he stood on a front-end loader. Later, he spoke from the occupied square’s main stage. But he was never a leader of the movement.

On Friday, he was already behaving as if he were the president-elect, meeting in Kiev with several European Union foreign ministers to discuss Ukraine’s economy before heading back to the campaign trail in his hulking black Mercedes. He said that he sought to unite Ukrainians and ethnic Russians, many of whom are distrustful of the government in Kiev, and that he welcomed talking to Russia’s leaders provided they recognize the elections.

“Immediately after the recognition of the elections, we are ready for dialogue” with Russia, he told reporters after his meeting with the European diplomats. He said he planned to protect the rights of Russian-language speakers and was skeptical about NATO membership, two key Russian demands.

But, he said, if instability continues in eastern Ukraine, he may re­evaluate his attitude toward NATO.

“Who knows,” he said. “Maybe we should make this decision.”

Election officials conceded Friday that just a small portion of voters in two violence-plagued eastern provinces would be able to vote, running the risk that the population there, already skeptical of the central government in Kiev, would feel even more disenfranchised.

But Russian President Vladimir Putin appeared Friday to retreat further from previous threats not to recognize the elections, perhaps calculating that a business tycoon who has major economic interests in Russia may be a cooperative negotiating partner in the future.

Still, Poroshenko will have to face critics from both flanks, not just Kiev skeptics in the east. Many anti-corruption Maidan activists fear that Poroshenko is a member of the old corruption-rife system of oligarchs they were trying to sweep away.

“The problem for Poroshenko is definitely that he is a strong businessman himself,” said Olexiy Haran, a professor of comparative politics at the National University of Kyiv-Mohyla Academy. “He is not as powerful as other oligarchs. But he still has a lot of business interests. The problem would be to separate business from politics.”

Witnesses said there was fresh violence Friday between pro- and anti-government militias in the village of Karlovka, about six miles beyond the city limits of Donetsk. Hours after the ­clashes, a restaurant damaged by heavy explosives was still smoldering, and shell casings littered the ground around a nearby gas station and an onion-domed church.

A pro-Russian separatist who took part in the fighting said four militants in his unit were killed when pro-Ukrainian fighters attacked a rebel checkpoint at a bridge. The rebel said at least 10 pro-Ukrainian fighters were also killed, a claim that could not be immediately verified. The violence came a day after fighting in the region killed at least 13 soldiers.

But the separatists who have seized government buildings around eastern Ukraine continued to come under pressure, from government security ­forces, pro-Kiev militias and residents who are increasingly furious.

“It’s a pity for both sides, for their children and their mothers who are crying,” said Alla Nikolenko, 45, whose home narrowly missed a direct hit by a shell Friday when fighting between pro- and anti-Kiev militias broke out shortly after 5 a.m. “We just want peace.”

Fredrick Kunkle in Donetsk and Abigail Hauslohner in Moscow contributed to this report.