Lee Hoi-chang has spent three decades with a gavel in his hand: 20 years as a judge and 10 as Korea's youngest Supreme Court justice.
When his second term with the Supreme Court ended in 1993, he became head of the Board of Audit and Inspection, which monitors public servants and government, and then prime minister to Kim Young-sam. Neither job lasted long.
Mr Lee, 62, felt he was not given enough power to carry out the inspector's job and President Kim fired him after five months for refusing to keep the nation's policy on North Korea private.
His 'Mr Clean' image helped him win the ruling party's first direct nomination this summer.
But his popularity then dropped with the news that neither of his sons had done their military service, and he has been an underdog since.
Though well respected, Mr Lee has had to work hard to soften his image, which some find too rigid and cold - unlike his wife, who is the most popular of the candidates' spouses.