South Korea's main opposition party has picked a former Hyundai boss and mayor of Seoul as its presidential candidate.
Lee Myung-bak, 65, won the nomination of the conservative Grand National Party (GNP) by a margin of 1.5%.
He is now considered a strong favourite to take the presidency in the election on 19 December.
The GNP is way ahead of the ruling left-leaning Uri party in opinion polls, as support for current President Roh Moo-hyun has plummeted.
Mr Lee told thousands of GNP supporters that they would take back the government.
"The GNP and I will hold hands with all who wish to join in our goals to achieve regime change and build a world-leading country," he said.
"We will regain the government. We will start a new Korea."
His main rival for the nomination, Park Geun-hye - daughter of a former military ruler, who hoped to become the country's first female president - conceded defeat.
"Now let's combine forces to help the party take power," she said.
Lee Myung-bak has a reputation for getting jobs done, and his forceful style while CEO at Hyundai earned him the nickname "the bulldozer".
He become mayor of Seoul in 2002 and won praise for tearing down an elevated highway he helped build at Hyundai to open up a stream running through the capital.
However, he has also been plagued by allegations of fraudulent land deals more than a decade ago - claims he denies.
Mr Lee has pledged to revive South Korea's sagging economy - a key reason for Mr Roh's fall in popularity - if he becomes president.
He has also said he will strengthen South Korea's relationship with the US, and backs a multi-billion-dollar plan for a cross-country waterway.
Although the GNP proposes a tougher line on North Korea than the current government, Mr Lee has promised a generous aid package if Pyongyang fulfils its pledge to end its nuclear programme.