Ukraine's presidential election is set for a second round run-off after partial results showed no candidate would win more than 50% of the vote. Analysts charge the results off to the Orange Revolution consequences.
A total of 18 candidates took part in the election.
With half the votes counted, former Prime Minister Viktor Yanukovych led current PM Yulia Tymoshenko by 37% to 24%.
The two were on opposing sides of the Orange Revolution in 2004-5, but both now favour closer ties with Russia.
Current President Viktor Yushchenko has been eliminated from the vote.
Turnout in the election was reported to be less than 50% by early afternoon.
In the capital Kiev, voters walked to polling stations through light snow. In the eastern city of Donetsk, one polling station encouraged voters with vodka and sausage.
The leading candidates have accused each other of trying to rig the election, and there have been warnings of unrest after the vote.
In an effort to boost confidence in the election, foreign observers have spread out across Ukraine to monitor voting.
Jens-Hagen Eschenbacher, of the Organisation for Security and Co-operation in Europe, said about 600 OSCE election monitors are in place, as well as thousands of other foreign observers.
The Orange Revolution led Ukrainians to expect sweeping changes - integration with Europe and an end to corruption, our correspondent says.
But the reality has not lived up to expectations and there is widespread disillusionment with politicians across the spectrum, he adds.
BBC News has contributed to the report.