The 2026 local elections, widely considered a litmus test for President Lee Jae Myung and his liberal administration, are finally here.Of all 4,241 posts up for grabs Wednesday, including 16 key executive seats and 14 parliamentary seats being contended in by-elections, The Korea Herald shines the spotlight on a select mix of heated battlegrounds.A loss in any of these spots could have significant ramifications for either of the two main parties, as well as the Lee Jae Myung administration itself. Chong Won-o (left) and Oh Se-hoon (Yonhap) Mayor of Seoul, capital city home to 9.3 millionChong Won-o, the Democratic Party of Korea's Seoul mayoral candidate, has long been the front-runner in opinion polls, but the polls also indicated Chong's lead against incumbent Seoul Mayor Oh Se-hoon narrowing.Chong served for 12 years as the chief of the Seongdong-gu District Office, the jurisdiction of which covers Seongsu-dong, where recent refurbishment projects have given it the nickname of "Seoul's Brooklyn."Chong quickly stepped into the media limelight after President Lee Jae Myung posted an X post in December that recognized Chong as a figure who "must be good at his job" as the district office chief.In part backed by Lee's de facto endorsement, Chong clinched victory in the party's internal competition, however, he has been embroiled in controversies over past violent behavior in 1995 and a business trip to Cancun, Mexico in 2023, among others.Chong is competing with the incumbent mayor, affiliated with the conservative People Power Party.Oh has been under fire for his launch of the Hangang Bus, a river bus network on the Han River, as it has suffered malfunctions and shutdowns multiple times.Recent findings concerning alleged construction glitches with the GTX-A commuter rail project in Gangnam-gu, Seoul, as well as the deadly collapse of the closed Seosomun Overpass while under inspection, have meanwhile left Oh -- seeking a fifth term as Seoul mayor for the first time in South Korea's history -- vulnerable to the ruling party's attacks. Chun Jae-soo (left) and Park Heong-joon (Yonhap) Busan, populous city with potential as maritime hubChun Jae-soo was the only liberal lawmaker to have been elected across all of the 18 constituencies in Busan in the 2024 general election.Standing out in the conservative stronghold, which is South Korea's second-most populous metropolitan city, Chun was appointed to become the first oceans minister in the Lee Jae Myung administration last year.He spearheaded the move to relocate the headquarters of the Oceans Ministry in line with Lee's policy initiatives to put an end to the polarization of national economic growth and turn Busan into an international maritime hub.Now, Chun is contending for the Busan mayoral seat, facing off against incumbent conservative Busan Mayor Park Heong-joon, who is seeking a third term. Kim Boo-kyum (left) and Choo Kyung-ho (Yonhap) Will liberal heavyweight make history in conservative stronghold Daegu?Kim Boo-kyum, the Democratic Party's candidate for the Daegu mayoral post, will walk an unprecedented path if he is elected mayor in the conservative stronghold.No liberal figure has been elected as Daegu's mayor since South Korea's introduction of local elections in 1995. But Kim, a former prime minister and four-term lawmaker, might be the closest that only liberal candidate has gotten to blazing that trail.He was already the first lawmaker elected in a district in Daegu in more than three decades. Kim served in the constituency of Suseong-A from 2016 to 2020, his fourth term as a seasoned lawmaker.Kim was also the runner-up in the 2014 Daegu mayoral election, but earned over 40 percent of the vote.Polls showed that Kim is now in a neck-and-neck race against Choo Kyung-ho, a former three-term lawmaker and floor leader of the People Power Party.However, the level of support for Choo appears to have recently been buoyed by former President Park Geun-hye's public appearance on his campaign trail. Lee Won-taeg and Kim Kwan-young (Yonhap) Surprise defeat in liberal stronghold of North Jeolla?Until a few months ago, few imagined that the liberal Democratic Party would ever lose a seat at the core of its stronghold.But recent opinion polls indicated otherwise, as independent candidate Kim Kwan-young is ahead in the race for the gubernatorial election in North Jeolla Province against opponents who include Lee Won-taeg of the Democratic Party.Kim, the incumbent governor of the region, was expelled from the ruling party during the candidate nomination process.Leaked footage suggested that Kim had been distributing cash envelopes to young party members and councilors in a restaurant. His supporters have posited that Lee had also been embroiled in a similar scandal, but the party went on to nominate him anyway. Kim Yong-nam (from left), Yu Eui-dong, Cho Kuk, Kim Jae-yeon and Hwang Kyo-ahn (Yonhap) Moon aide's bid for parliamentary seat in Pyeongtaek-BCho Kuk, a close aide to former President Moon Jae-in contending in a parliamentary by-election, is seeking a dramatic comeback to the National Assembly.A longtime aide of the former liberal president and advocate for prosecutorial reform, Cho fell from grace after an academic credentials forgery scandal involving his family drew public backlash in 2019.Cho returned to politics in May 2024 when he was elected as the lawmaker of the minor liberal party he founded, the Rebuilding Korea Party. However, his conviction at the top court in December the same year forced him to leave the National Assembly.This time, Cho is seeking redemption as the Rebuilding Korea Party candidate for a parliamentary seat in the Pyeongtaek-B electoral district.Cho will have to overcome a crowded field. Also on the same ballot are former lawmaker Kim Yong-nam for the Democratic Party, a former lawmaker who represented the district and candidate from the People Power Party Yu Eui-dong, minor Progressive Party leader Kim Jae-yeon and Hwang Kyo-ahn, a former prime minister and prominent far-right figure. Ha Jung-woo (from left), Park Min-shik and Han Dong-hoon (Yonhap) Busan's Buk-A by-election steals piece of the spotlightEyes are also glued to whether Han Dong-hoon, an independent candidate in Busan's Buk-A parliamentary by-election, could enter the National Assembly.Han, a longtime ally who had a falling-out with impeached and removed President Yoon Suk Yeol, previously served as the chair of the People Power Party and led the right-wing party in the 2024 general election campaign.Han stepped down from the chair position soon after a motion to impeach Yoon in the wake of the December 2024 martial law crisis passed the National Assembly, with some lawmakers in his camp voting in favor.Just over a year later in January, Han was expelled from the party he had chaired over internal criticism of Yoon.Now, as the independent candidate and front-runner in the parliamentary by-election, Han is squaring off against the Democratic Party's Ha Jung-woo, who recently stepped down as senior presidential secretary for artificial intelligence and future planning, and the People Power Party's Park Min-shik, a former veterans affairs minister.