SEOUL — South Korea's ruling Democratic Party suffered a devastating defeat in Wednesday's mayoral by-elections, widely considered a bellwether for next year's presidential race.

President Moon Jae-in's party lost both by large margins in the capital Seoul and the country's second biggest city, Busan, to the conservative opposition People Power Party (PPP).

In Seoul, the PPP's Oh Se-hoon won 57.5% of votes and made a victorious return to the office he served between 2006 and 2011. His competitor, Park Young-sun, a woman who worked as a minister in Moon's government, took 39.2% of votes. In Busan, conservative Park Heong-joon won 62.7% of votes against liberal Kim Young-choon's 34.4%.

The ruling party had won all fourmajor elections since 2016, including a landslide in parliamentary polls last April. But support for Moon and his party has been steadily eroding since then.

Over the past year, initial praise for Moon's handling of the COVID-19 pandemic gave way to growing economic woes, especially soaring housing prices. The public's exasperation was heightened by a land speculation scandal involving a government housing development agency that erupted just a month before the by-elections.

Moon said in a statement on Thursday that he "sternly accepts the nation's reproach" in the elections and vowed to tackle critical issues such aseconomic recovery and eradication of real estate corruptions.

However, the president failed to address one of the largest issues looming over Wednesday's polls — gender. The two former mayors of Seoul and Busan, both representing the DP, relinquished their positions after female staffers accused them of sexual harassment. Seoul's former mayor, Park Won-soon, took his own life following the accusations.

The party's initial reluctance to admit Park's wrongdoing and protect the accuser from those who questioned her motivation apparently turned off voters.During the campaign period in Seoul, the party's mishandling of the sexual harassment allegations drew the ire not onlyof the main opposition but from four minor-party women candidates, all at least 15 years younger than the DP candidate Park Young-sun, who is 61.

While the four women collectively won just 1.8% of total votes, they represent a record number of female candidates in Seoul's mayoral elections — five including Park Young-sun — and the desire of younger female voters to be heard.

Wednesday's exit polls showed that 15.1% of women aged 18 to 29 voted for candidates outside the two major parties. That figure is singularly high compared to other demographic groups, who all gave less than 6% support to independent or minor-party candidates. It also reflects some young women's breakaway from the DP, which has traditionally enjoyed strong support from younger female voters.

But the voices of women are unlikely to be heard any more clearly by either ofthe major parties after the election, said Kwon Soo-hyun, the director of civic group Korea Women's Political Solidarity. She said that the DP is more concerned about young male voters, who have increasingly become conservative over the past decade. They cast more than 70% of ballots for the opposition on Wednesday. Meanwhile, the PPP's gender policies signal no structural reform beyond addressing some minor complaints.

In a victory speech on Thursday, Seoul's new mayor, Oh Se-hoon, promised to see to it that the female staffer who was the victim of his predecessor's sexual harassment returns to work immediately.

Kwon said she doesn't believe "gender equality will be his core value as the new mayor runs the city government," but added, "I hope he makes sure to keep his promise and to remember it if ever a similar incident were to happen."

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