Taiwan's president, Chen Shui-bian, has won re-election by an extremely narrow margin, one day after surviving an apparent assassination attempt. But, Taiwan's High Court has ordered the sealing of ballot boxes following his opponent challenge of the results.

Supporters of President Chen Shui-bian cheer as the vote tallies come in. Mr. Chen defeated his rival, Lien Chan, by a margin of less than a percentage point.

Observers say the president was helped by a sympathy vote, after he was slightly wounded in an apparent assassination attempt Friday.

But Mr. Lien said the election was unfair. Mr. Lien said there are so many uncertainties about the election that he and his party have decided to try to have it declared invalid.

Amid fear of unrest over the controversy, Mr. Lien also urged supporters to remain calm, though some small pro-Lien demonstrations took place in the evening.

Mr. Chen campaigned on a platform emphasizing Taiwan's sovereignty apart from China, which considers the island part of its territory.

Taiwan split from the mainland in 1949, when Nationalists fled to the island following the Communist Party's takeover of China.

Beijing has been a sharp critic of President Chen in the past, though it remained relatively quiet about Taiwan in the weeks before the election.

David Huang, a scholar with Taiwan's top government research institute, Academia Sinica, says President Chen's re-election may push China to rethink its stance.

"Probably, they have to think," he said. "Well, if you continue to try to resist the Chen administration, you will not in the end get anywhere.' So, they will probably have some policy revisions."

The island also voted the same day on a referendum on whether to set up a mechanism for talks with China and whether to increase national defenses against Chinese missiles aimed at Taiwan.

However, the referendum failed to receive the support of 50 percent of registered voters, as required for passage.

President Chen had called the referendum more important than his re-election. But despite its defeat, he said the result was close enough to show a plurality of support for the referendum.

Officials in Chen's government said earlier that the referendum was, in any case, more of a symbolic democratic exercise, and was not necessarily binding in terms of policy.