By Hyonhee Shin
SEOUL, April 8 (Reuters) - South Korean President Moon Jae-in's ruling party suffered a devastating defeat in a special election for key mayoral posts amid political scandals and policy blunders, vote counts showed on Thursday.
Millions of South Koreans went to the polls on Wednesday to elect chiefs of the country's two largest cities, the capital Seoul and port city of Busan, among 21 local offices up for grabs.
The election was widely seen a key barometer for potential political shifts for Moon's progressive party with less than one year before the March 9 presidential election.
Moon and his Democratic Party have seen their approval ratings plunge to record lows in recent months amid skyrocketing housing prices, deepening inequality, sex abuse scandals and souring ties with North Korea.