Ukraine election officials say, with almost all votes counted, pro-reform opposition candidate Viktor Yushchenko has swept Sunday's re-run presidential election - defeating pro-Russia Prime Minister Viktor Yanukovych.

With more than 90 percent of votes counted, Ukraine's Central Election Commission says Viktor Yushchenko has a 13-point lead over Prime Minister Yanukovych - making victory apparent.

Sunday's vote was a repeat of November's presidential run-off - won by the pro-Russian prime minister. But that vote was ruled invalid by the Supreme Court due to massive voter manipulation and fraud.

The election commission says opposition leader Yushchenko garnered 55 percent of the vote compared to Mr. Yanukovych's 41 percent among Ukraine's 38 million registered voters. Some 77 percent of voters turned out to cast ballots for the third time.

After the long and bitter electoral process, Mr. Yushchenko wasted little time claiming victory. He first appeared at his headquarters overnight, with his wife by his side, to say the result was really a win for Ukrainian democracy.

Later he visited Kiev's Central Independence Square, where tens-of-thousands of his supporters had gathered in a celebratory mood waving banners of the campaign's trademark color orange. He told them Ukraine was now free from a political era he said had been marked by cynicism and lies.

Mr. Yushchenko says the results, though still not complete, show the power of Ukraine's people - a people he has promised to lead into the Western community of democratic nations. He campaigned on a pledge to secure Ukrainian membership in the European Union and NATO. But he says his first task will be to heal the nation which, at one point during the campaign, threatened to split.

Pro-Russia Prime Minister Viktor Yanukovych has not conceded defeat, but earlier said he would serve in a new opposition movement in the event he was not declared the winner of Sunday's election. He has also refused to rule out further legal challenges to the latest vote.

Sunday's poll passed relatively peacefully, despite high tension and possible fears of violence. A record 12,000 plus observers were on hand to ensure that the vote was free and fair this time around.

Western observers are expected to give their assessment of Ukraine's election process - a vote closely watched by not only Europe and the United States, but by Ukraine's largest neighbor, Russia.

Videoreportage by Jeff Swicord