SEOUL -- Lee Jae-myung, presidential candidate of South Korea's majority liberal Democratic Party, would be elected the country's new president with certainty, local broadcaster JTBC and three terrestrial broadcasters said Tuesday.

Lee made a short speech to supporters near his house before heading for the National Assembly building in central Seoul, saying that he paid respect to "people's great decision."

He vowed to fulfill his responsibilities and missions to live up to people's expectations.

With 45 percent of the votes counted at 11:52 pm local time (1452 GMT), Lee won 49.10 percent and his archrival Kim Moon-soo of the conservative People Power Party took 42.55 percent, the National Election Commission data showed.

A joint exit poll, conducted by three terrestrial broadcasters including KBS, MBC and SBS, showed Lee leading with 51.7 percent of the votes over Kim with 39.3 percent.

Preliminary voter turnout reached 79.4 percent, marking the highest in 28 years since the voting rate recorded 80.7 percent in 1997.