After a protracted delay, the Ukrainian Central Elections Commission announced Wednesday that the leading opposition candidate for president, Viktor Yushchenko, won the first round of voting on Oct. 31, coming in a half-percentage point ahead of Prime Minister Viktor Yanukovych.

Yushchenko, a former prime minister who supports integration with the West, had 39.87 percent of the vote compared to 39.32 percent for Yanukovych, who is widely seen as the Kremlin's favored candidate. He favors close ties with Russia.

Preliminary results showed Yanukovych with the lead, but many of the votes that were counted late, due to charges of fraud, were in Yushchenko strongholds, his supporters said. Because neither of the two candidates received 50 percent of the vote in a field of more than 20 candidates, a runoff will be held Nov. 21.

The electoral commission said its final result accounted for 97 percent of the ballots cast. The remaining 3 percent were disqualified because of what the body's chairman described as "grave voting irregularities" in some districts.

Both Yanukovych and Yushchenko are now seeking support from minor party candidates. Yushchenko has secured the backing of the Socialist Party leader, Oleksandr Moroz, who received nearly 6 percent of the vote in the first round, and former prime minister Anatoly Kinakh, who received less than 1 percent. Yanukovych hopes to gain the support of voters who opted for the Communist Party candidate in the first round, his advisers said.

Even with his victory in the first round official, Yushchenko continued Wednesday to question the validity of the results. "It is morally important for very many people how the first round ended," he said at a briefing in Kiev, the capital. "It is a question of who won despite all the vote-rigging."

As the second round of voting drew near, the rival camps continued to trade charges of cheating. Yanukovych filed a complaint with the election commission Monday, saying a weekend rally by Yushchenko supporters violated a law against campaigning until final results of the first round were announced.

The television station ICTV reported that a land mine was found Tuesday near the home of Volodymyr Syvkovych, a member of parliament and a Yanukovych supporter. He headed a commission that looked into an alleged poisoning that took Yushchenko off the campaign trail for several weeks in September and October. Syvkovych has dismissed Yushchenko's charge that he was poisoned by unnamed officials.