That poll was conducted under a program funded by several Western governments, including the United States. It was based on responses by 20,000 voters at polling places throughout the country.
An exit poll carried out by a government-linked polling agency also shows Yuschenko ahead, though by a narrower margin -- 49.4 percent to 45.9 percent.
Other exit polls by government-affiliated entities are showing Yanukovych ahead by various percentages. Official results are not expected for several hours.
The election was tense, with supporters from both sides claiming widespread irregularities. Election Commission officials say the voting turnout was strong.