SEOUL, South Korea - A former Hyundai CEO known as "The Bulldozer'' for his determination to get things done rolled over both his opponents and fraud allegations Wednesday to win South Korea's presidency and end a decade of liberal rule.

Lee Myung-bak, a former Seoul mayor who turned 66 on election day, earned the landslide victory on a wave of discontent with incumbent President Roh Moo-hyun, whom many believe bungled economic issues and dragged down the country's rapid growth.

The rise to power of Lee's conservative Grand National party was expected to herald closer ties with Washington and a more critical view of relations with communist North Korea, which has been lavished with aid by Roh's administration.

The National Election Commission said Lee had won 48.7 per cent of the vote with 99.9 per cent of ballots counted. Liberal Chung Dong-young was a distant second with 26.2 per cent, while independent Lee Hoi-chang was well behind that.

It was the biggest margin of victory ever in a South Korean presidential election, officials said.

Voters apparently wanted change so badly that they were willing to overlook accusations of ethical lapses that dogged Lee throughout the campaign.

Just days before the election, parliament approved an independent counsel investigation into allegations that Lee manipulated stock. The investigation is to be completed before the Feb. 25 inauguration, and Lee has said he will step down if found at fault.

"After all, the people chose the economy over morality,'' the Maeil Business Newspaper wrote in an editorial for its Thursday editions.

Lee emphasized the economy in his campaign with a "747'' pledge _ promising to raise annual growth to seven per cent, double the country's per capita income to $40,000 and lift South Korea to among the world's top seven economies.

He also proposed a "Grand Canal'' linking Seoul to the southern port city of Busan that would improve transport and be a tourist attraction.

"Today, the people gave me absolute support. I'm well aware of the people's wishes,'' Lee told supporters at his party's headquarters. "I will serve the people in a very humble way. According to the people's wishes, I will save the nation's economy that faces a crisis.''

Hundreds of supporters watching the results on a giant TV in front of the Grand National party's headquarters burst into song Wednesday evening as Lee's victory became clear.

"I am very happy and it is like retaking democracy after a decade'' of liberal rule, said Park Mi-won, a housewife in her 50s.

Lee rose from the poverty that gripped the peninsula after the 1950-53 Korean War and worked as a janitor to put himself through college.

He first gained prominence as head of Hyundai's construction unit, which symbolized South Korea's meteoric economic rise in the 1960-70s. As Seoul's mayor from 2002-2006, he undertook beautification projects in the city that earned him environmental credibility and were viewed as redemption for earlier eyesores he built with Hyundai in the country's haste to develop.

It was during his three decades with the Hyundai Group that Lee earned the nickname "Bulldozer'' for his drive to push through challenges. In one instance, he completely took apart a bulldozer to study its mechanism and figure out why it kept breaking down.

Lee heads to office amid progress in the long-running standoff over North Korea's nuclear weapons program, fostered by U.S. political and economic concessions to Pyongyang.

The president-elect is expected to tie aid to continued compliance with international demands in the atomic dispute in line with Washington's wishes, but was not expected to make any dramatic change in assistance while the North remains on the path to disarmament.

The Bush administration congratulated Lee on his victory, saying it expected close co-operation with his government over the North Korean nuclear dispute.

Taking the luster off Lee's victory were lingering allegations of involvement in a stock manipulation case in which a former business associate faces criminal charges for illegal gains of millions of dollars. A video released Sunday by his liberal rivals showed Lee saying in 2000 that he founded the firm at the centre of the case.

Lee has said the taped comments were taken out of context and denied the allegations, but consented to the independent counsel to clear his name. He is the country's first president-elect to face a criminal probe.

By South Korean law, a president-elect can be prosecuted but he would receive immunity from most criminal lawsuits after inauguration.