Petro Poroshenko, a veteran deal maker who has vowed to end politics as usual, greets supporters at a rally Sunday in the city of Zaporizhzhia. Mykola Lazarenko/Press Pool
With Ukraine's presidential vote less than a week away, front-runner Petro Poroshenko says he knows the first step to pulling together the fractured country: Elect him in the first round of voting.
Ukraine's survival, he says, all but depends on it.
It is a message the 48-year-old billionaire and politician has been repeating as he hopscotches across eastern parts of Ukraine in his private jet with his wife and a clutch of advisers. His message resonates with a worried public in Dnipropetrovsk, not far from regions further east that have been declared separatist republics by pro-Russia militias.
It remains unclear whether the Chocolate King—Mr. Poroshenko's nickname because of the Roshen confectionary empire he owns—can surpass the 50% threshold of votes required on Sunday to prevent a runoff against his rival and second-place candidate, former Prime Minister Yulia Tymoshenko.
One recent poll suggested he would get 54.7% of the vote, which would deliver him a first-round victory, but earlier polls have said otherwise. A runoff, Mr. Poroshenko has warned, would likely spell months of delays when Ukraine can't afford any more uncertainty.
He is running for president in a country that has lost territory in Crimea and gained a separatist pro-Russia rebellion in the east—all in the three months since pro-Europe demonstrators in the capital toppled former President Viktor Yanukovych.
Mr. Poroshenko emerged as perhaps the brightest leader after those demonstrations and built a campaign promising to meet the protesters' demands for a political overhaul. But he has now found himself fighting for the survival of his country.
Whether the next president can end politics as usual in Ukraine—with its oligarch clan warfare, deep-seated corruption and paralyzing infighting—will be a key factor in Kiev's bid to move toward Europe and avoid further encroachment by Russia.
A win for Mr. Poroshenko would place the country in the hands of a veteran of Ukraine's sordid political arena who has earned a reputation as a deal maker prepared to ally with lawmakers of all stripes. Supporters say that experience gives him the skills to maneuver and execute pressing reforms. Critics say his history signals a return to the same old politics that for years have hobbled Ukraine.
"He doesn't have an ideology," said Oleh Rybachuk, a civil activist and former Ukrainian deputy prime minister. "Does he have managerial capabilities? Yes he does. Does he have political instincts? Yes he does." A spokesman for Mr. Poroshenko declined to make the candidate available for an interview.

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  • Petro Poroshenko: Nicknamed the "Chocolate King," the billionaire owner of the Ukrainian confectionary firm Roshen has served as foreign minister, secretary of the national security and defense council and trade minister.
  • Yulia Tymoshenko: Known as Ukraine's "Orange Princess" for her role in the 2004 Orange Revolution, the former prime minister was released from prison after former President Viktor Yanukovych was toppled in February.
  • Serhiy Tihipko: Mr. Tihipko is a billionaire banker and member of Ukraine's parliament who at times was allied with Mr. Yanukovych and in 2004 ran his presidential campaign.
  • Anatoliy Hrytsenko: A member of Ukraine's parliament, the longtime military man served as minister of defense in a number of administrations, including when Ms. Tymoshenko was prime minister.
Mr. Poroshenko is certainly one of the country's foremost political survivors. The chocolate magnate supported then-President Leonid Kuchma in the late 1990s and early 2000s before joining the movement that toppled him. He then served as foreign minister under former President Viktor Yushchenko —the godfather of his daughters and Mr. Kuchma's successor. Later, he became trade minister under Mr. Yanukovych before leading the pro-Europe protests that toppled him in February.
Despite this veteran status, Mr. Poroshenko's campaign slogan—"Live Differently!"—promises a break from the past. He pledges to salvage Ukraine's economy by following a trade pact with the European Union and an International Monetary Fund recovery program.
He says he has plans to make Ukraine so prosperous that Crimeans "will realize their mistake" and return on their own. To solve the crisis in the separatist regions of the east, he has proposed using force against the rebels, whom he calls terrorists, and changing the constitution to appease residents of those regions with more autonomy.
Still, many residents of Ukraine's east say they don't plan to vote because no candidate represents their interests, calling into question whether the presidential election can help unite the fractured country. Separatists, meanwhile, have vowed to prevent the vote in the Donetsk and Luhansk regions.
Elsewhere, some see Mr. Poroshenko as the best, if not ideal, choice. "Whether people like him or not, most think he is the least bad of the alternatives," said Andrey Bogatyryov, chief editor at Populyarnaya Gazeta in Dnipropetrovsk.
Born in a town near the Ukrainian border with Romania, Mr. Poroshenko found success in business after the Soviet Union's collapse, initially by importing cacao and later building a candy company that became Ukraine's largest. His sweeping business interests grew to include a bus maker and television station. In early 2013, Forbes magazine's Ukrainian edition put his net worth at $1.6 billion.
Mr. Poroshenko, like most of Ukraine's presidential candidates, comes with political baggage. After entering parliament in 1998, he helped establish the Party of Regions, the political party that backed Messrs. Kuchma and Yanukovych. He broke with the party to ally with Mr. Yushchenko and support the pro-Western Orange Revolution in 2004.
The tycoon developed a deep rivalry with Ms. Tymoshenko, the Orange Revolution partner who bested him in 2005 for the prime minister post. Their conflict exploded into public that year with mutual recriminations that helped lead to the government's dispersal. He later served as foreign minister under Mr. Yushchenko and trade minister under Mr. Yanukovych.
It wasn't until last year, however, that Mr. Poroshenko's political fortunes truly began to rise. Russia banned imports of his Roshen chocolate, ostensibly because of its poor quality despite international certification. Many viewed the ban as an effort by the Kremlin to warn Ukraine against signing a European trade pact. The massive losses Mr. Poroshenko suffered built his profile and made him a face of the pro-Europe fight.
Then, Mr. Yanukovych refused to sign the European pact—which Mr. Poroshenko has said he wrote—causing thousands of people to protest in Kiev.
When some demonstrators attempted to use a tractor to break through police lines, Mr. Poroshenko climbed onto the vehicle and called for calm. Speaking through a small orange loudspeaker, his voice was barely audible amid boos and whistles, but the intervention shot him to the forefront among the protests' political leaders. He was the only one of the country's richest tycoons to throw his weight so clearly and forcefully behind the protesters' cause.
Boxer and political newcomer Vitali Klitschko, who had expected to be the main challenger to Mr. Yanukovych in 2015 elections, failed to become the clear leader of the movement against the president, in part because of his wooden speeches that did little to electrify the crowds.
After Mr. Poroshenko leapfrogged him in polling in March, Mr. Klitschko bowed out of the presidential race. He threw his support behind Mr. Poroshenko and entered the race for Kiev mayor. Mr. Klitschko's political team now works for Mr. Poroshenko's campaign.
Part of Mr. Poroshenko's appeal is his business background. Ukrainians may be suspicious of the country's tycoons, but they lately have been seen as a mainstay against Russian aggression, with a few appointed as caretaker governors of eastern regions. At each of his rallies, Mr. Poroshenko repeats that workers in his candy company make 7,000 hryvnia ($595) a month, a gob-smacking amount for most Ukrainians, whose average wage is around 3,300 hryvnia.
At a recent appearance, the tycoon and his squad of bodyguards waded through the audience to the stage. He then spoke for more than 40 minutes, rousing the crowd with promises to revive the army and the economy and raise living standards. Written questions from the crowd, putatively spontaneous, were the same as at other rallies: Why not ban the Communist Party? Why are the same bureaucrats in power as before? How will Ukraine regain Crimea?
Mr. Poroshenko explained: "There are no easy answers."
—James Marson contributed to this article.
Write to Alan Cullison at, Paul Sonne at paul.sonne@wsj.comand Katya Gorchinskaya at