Hyung-Jin Kim Members of South Korean ruling Democratic Party watch screens showing the result of exit polls of the Seoul mayoral by-election at the party headquarters Wednesday, April 7, 2021, in Seoul, South Korea. (Jung Yeon-je/Pool Photo via AP) April 08, 2021 - 2:40 AM SEOUL, Korea, Republic Of - South Koreaâs conservative opposition party has won sweeping victories in mayoral byelections in the countryâs two biggest cities, a blow to President Moon Jae-in ahead of next yearâs presidential vote. Oh Se-hoon of the opposition People Power Party won 57.5% of the votes cast in Wednesdayâs election in Seoul, the capital city, according to the final vote tally released by the National Election Commission. Park Young-sun of the ruling Democratic Party won 39.2% of the votes.