Former Ukrainian Prime Minister Viktor Yanukovych looked set to clinch the presidency Sunday, with early exit polls giving him a narrow lead, although his longtime rival, Prime Minister Yulia Tymoshenko, promised to challenge results from the front-runner's strongholds.
Yanukovych was leading with 48.7 percent of the vote, compared with 45.5 percent for Tymoshenko, according to the National Exit Poll, which surveyed more than 15,000 voters. The poll, released when voting closed at 8 p.m. local time, had a margin of error of 2.5 percentage points.
Other polls showed Yanukovych with a similarly narrow lead.
The new president, elected to a five-year term, faces the difficult task of improving relations with both Russia and the European Union while trying to rebuild a shattered economy. The winner could also have trouble forming a government that will be able to break the country's political deadlock.
In the election's first round, Yanukovych had about 35 percent of the vote, while Tymoshenko won 25.5 percent. Neither candidate managed to win support from their nearest competitors.
Close to 50 percent of voters had cast ballots by 3 p.m. local time, according to the latest data available from Ukraine's Central Election Commission.
A victory would mark a major comeback for Yanukovych, who won the 2004 presidential elections in a fraud-tainted vote that was overturned by the Orange Revolution. After weeks of mass street protests, led by Tymoshenko and outgoing President Viktor Yushchenko, the Supreme Court threw out the results and ordered a new election.
But the revolution — driven by strong pro-democracy sentiment — also created a dangerous precedent for Ukraine, and Yushchenko warned voters Sunday that the most important result would be a peaceful and democratic handover of power.
Those concerns were underscored on election day, with campaigners for Yanukovych and Tymoshenko accusing their opponents of fraud and other campaign violations from the morning on. Tymoshenko said Thursday that she would call for new street protests if she suspected fraudulent results, although analysts are skeptical that disenchanted voters would be as supportive as they were in late 2004.
Tymoshenko's campaign manger, Oleksandr Turchynov, said late Sunday in Kiev that it was "too early" to call a winner, especially amid the campaign's concerns of election violations. But supporters of Yanukovych were saying Tymoshenko should concede and that any attempt to challenge the results would be posturing to secure a position in the government.
Yanukovych, 59, went to a polling station in Kiev with several deputies from his Party of the Regions, which draws its strongest support from Russian-speaking industrial areas in the east.
"I'm sure that the Ukrainians deserve a better life. That's why I voted for good changes, stability and a strong Ukraine," Yanukovych told reporters at the polling station, located at an art school.
Tymoshenko cast her ballot in her hometown of Dnipropetrovsk, some 450 kilometers southeast of Kiev, with her husband and daughter.
“I congratulate everybody for taking part in democracy,” Tymoshenko said. "I've voted for a new Ukraine, prosperous and European, where people will live happily. I'll serve Ukraine with my all soul."
Observers from the Commonwealth of Independent States Election Monitoring Organization appealed to the Central Electoral Commission to take note of Tymoshenko's "open campaigning" on election day, which they called a "major violation."
But domestic and international observers reported no major issues as of Sunday evening. The Organization for Security and Cooperation in Europe, which led a mission of 650 international observers, scheduled a news conference for Monday.
State Duma Deputy Speaker Alexander Babakov, a deputy from the Just Russia party who headed the chamber's delegation to monitor the election, said the voting was being held in a "calm and democratic atmosphere."
In one of the more noteworthy disturbances, however, four women of the Femen female movement protested at Kiev's polling station No. 20, where Yanukovych cast his ballot. The women stripped to their waists and chanted, "Stop raping the country," before being led off by officials.
The Ukrainian Embassy in Moscow was flooded with voters, with hundreds lined up outside by late morning. A policeman guarding near the line said there were "many more people than at the first ballot" in January. The embassy reported that more than 2,500 voters cast ballots.
The pro-Kremlin youth movement Young Russia held a demonstration near the embassy during the afternoon calling for closer relations between Russia and Ukraine.
Verkhovna Rada Speaker Volodymyr Lytvyn, leader of the People's Party, said he doubted that the new president would be able to carry out any reforms given the complicated situation that Ukraine is facing politically and economically.
"The winner will be trapped because there will be about six or seven months left until the end of 2010 to accomplish any radical measures. … He or she will be a hostage of promises," Lytvyn told reporters at a polling station, Interfax said.
Yushchenko's presidency was a rocky one, with Russia cutting off gas supplies twice — seriously hurting both countries' reputations as reliable energy partners.
Additionally, the economic crisis has hit Ukraine as hard as anywhere in Europe, with the government expecting a 15 percent fall in last year's gross domestic product. The new president will have to build up a government coalition able to unfreeze the International Monetary Fund’s emergency loan of $16.4 billion, which the IMF blocked late last year after lawmakers failed to pass a budget for 2010 or cut spending.
But analysts said horse-trading was likely to continue for at least the next few days. Election officials must declare a winner by Feb. 17, and the president-elect would take office 30 days after the announcement.
Tymoshenko's camp said she would challenge votes cast at more than 1,000 polling stations, or about 3 percent of the total, which could be enough to throw the outcome into doubt, The Associated Press reported. Tymoshenko's supporters were prevented from joining election boards, primarily in the eastern regions of Donetsk and Lugansk, the report said.
Turchynov said Yanukovych's team was using "criminal" methods, according to a statement on the campaign's web site.
Ukrainian police said thousands of Yanukovych's supporters were heading to Kiev for a Monday demonstration.