SEOUL – A technology entrepreneur-turned-professor whose independent candidacy shook up South Korea's presidential campaign announced late Friday that he was dropping out, leaving the Dec. 19 election as a race between candidates from the country's two main political parties.

Ahn Cheol-soo said in a hastily-called news conference that he was exiting because voters needed one liberal-leaning candidate to compete with the conservative nominee, who has been favored in a three-way contest.

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