Why it matters. Seoul's mayoralty is South Korea's second most powerful elected office and a frequent springboard to presidential politics, so control of the capital shapes the national balance of power.
Background. The June 3 vote was a nationwide local election. Oh Se-hoon leads the conservative People Power Party (PPP); Jung Won-oh represents the liberal Democratic Party (DP), which controls the national government, making Seoul a high-stakes check on it. Oh framing his win as a 'safety valve of democracy' reflects this opposition-vs-ruling-party dynamic.
What to watch next. Watch whether the PPP pursues legal challenges or investigations over the ballot shortage now that it no longer affects the result, and how accountability falls on the National Election Commission.
Oh Se-hoon overtakes rival to win Seoul
Oh Se-hoon of the conservative People Power Party (PPP) was elected mayor of Seoul on June 4, securing his fifth electoral win, after a razor-thin overnight count in South Korea’s June 3 local elections reversed exit-poll projections that had favored his liberal challenger, Jung Won-oh of the Democratic Party (DP). With counting near complete, Oh took about 48.9% of the vote (roughly 2.50 million ballots) to Jung’s 48.3% (about 2.47 million), a margin of just over 30,000 votes.
The result was a genuine come-from-behind win. When the three main broadcasters released their joint exit poll at 6 p.m. on June 3, Jung was shown leading. Oh did not pull ahead until the early hours of June 4 and only locked in the victory mid-morning, helped by late returns from Songpa, a wealthier southern district where conservative support runs relatively strong and where vote-counting lagged the rest of the city.
Jung conceded at 9:30 a.m. from his campaign office in central Seoul. “I take the citizens’ choice gravely and humbly,” he said, adding, “I fell short. Everything is my fault.” He congratulated Oh and apologized to supporters and volunteers. The Hankyoreh’s coverage captured the split mood of the day — cheers from city-hall staff for the returning mayor, and a bowed head from the defeated challenger.
A victory shadowed by a ballot-shortage scandal
Around 9:50 a.m., Oh delivered his victory speech from his office in Jongno, central Seoul, then walked to Seoul City Hall, where staff greeted him with applause and flowers. He called the win “a victory of common sense” and said voters had kept Seoul as “the last safety valve of democracy,” framing the result as a reassertion of checks and balances against a Democratic-led national government. He insisted the outcome was “not a personal victory.”
But the election was clouded by a ballot-paper shortage. On voting day, several polling places — in Seoul’s Songpa district, in Incheon, and in Hwaseong in Gyeonggi province — ran out of ballots, forcing some sites to extend voting until 10 p.m. Oh acknowledged the problem directly, calling it a “serious flaw” that “cannot be buried as if nothing happened” and an infringement of voters’ rights that demands a thorough investigation and “grave accountability.”
The PPP’s about-face on a re-vote
The Hankyoreh drew a sharp contrast between the PPP’s tone before and after the result. On the night of June 3, with Jung still ahead in projections, senior PPP figures had loudly demanded a halt to vote-counting and a fresh election. Floor leader Song Eon-seok called an emergency briefing citing election law and a German precedent — a Berlin regional vote that the country’s constitutional court annulled over administrative failures. Party leader Jang Dong-hyeok said the vote’s “fairness is already broken,” while lawmakers Na Kyung-won and Kim Eun-hye posted late-night calls for a re-vote.
Once Oh’s win was confirmed, those demands quietly vanished. Song’s morning statement said the party “humbly accepts the will of the people” and dropped any mention of a re-election, pivoting instead to calls for accountability at the National Election Commission. Na and Kim posted nothing further. DP lawmaker Jeon Yong-gi seized on the shift, asking whether the PPP still wanted a re-vote now that counting was done, and accusing it of “shaking the democratic system itself for political gain.”
Back to work amid safety concerns
Oh said he would return to City Hall immediately. He named the Samseong Station rebar-omission case — a construction-safety controversy he argued had been “distorted” during the campaign — as an early priority. Following the collapse of the Seoseomun overpass in central Seoul during the campaign, he also pledged a high-intensity special safety inspection of all aging infrastructure and construction sites across the city.
