SEOUL-- The ruling People Power Party (PPP) was on course to claim a landslide victory in Wednesday's local elections, leading in 13 out of the 17 key races, including those for Seoul mayor and Gyeonggi governor.

With about 25 percent of the vote counted, the main opposition Democratic Party (DP) was leading only in four key races, including three in its stronghold of the Jeolla provinces, a painful defeat following March's narrow presidential election loss.

The PPP was also leading in five of the seven parliamentary seats in by-elections held simultaneously.

The elections took place less than a month after President Yoon Suk-yeol took office. The results, if finalized, are expected to significantly strengthen the mandate of the new government as it pushes its agenda in its first years.

Up for grabs in this year's local elections were 17 metropolitan mayoralties and provincial governorships, 226 lower-level administrative leadership positions, as well as 872 seats in provincial and metropolitan councils, and 2,988 in lower-level local councils.

Also at stake were seven National Assembly seats in parliamentary by-elections.

Of the many battlegrounds, both parties view the capital area as the most important, as half of the country's population resides there.

With 8.39 percent of the ballots counted, incumbent Seoul Mayor Oh Se-hoon of the PPP, led the election with 55.32 percent of the vote against Song Young-gil of the DP with 43.17 percent.

In the Gyeonggi governor race, where 23.13 of the ballots were counted, Kim Eun-hye of the PPP led with 50.72 percent against the DP's Kim Dong-yeon with 47.16 percent.

Ballots counted also indicated the ruling party candidates' win in 12 other major cities and provinces -- including the cities of Incheon, Busan and Ulsan and the provinces of Chungcheong.

The DP was ahead in only three of its strongholds -- the city of Gwangju and the Jeolla provinces -- as well as the Jeju governorship.

In parliamentary by-elections, former presidential candidates Lee Jae-myung and Ahn Cheol-soo were near clinching their National Assembly seats.

Their parliamentary races carry extra significance since the victory could help them gain ground in their respective parties and pave the way to another shot at the presidency.

With nearly half of the ballots counted, Ahn of the PPP, who withdrew from the presidential race to endorse Yoon, virtually secured the seat representing the Bundang-A district of Seongnam, just south of Seoul, by winning 64.8 percent of the vote against DP's Kim Byoung-gwan with 35.2 percent

With 9.1 percent of the ballots counted, Lee of the DP, who lost to Yoon in the March 9 presidential election by a razor-thin 0.73 percentage-point gap, was moving closer to win the seat in the Gyeyang-B district in Incheon, west of Seoul, by taking 55.1 percent of the vote against PPP's Yoon Hyung-sun with 44.8 percent.

Voting took place from 6 a.m. to 6 p.m. at 14,465 polling centers nationwide, except for COVID-19 patients and those in self-isolation who cast their ballots from 6:30 p.m. to 7:30 p.m.

Vote counting began around 8:40 p.m. at 255 ballot counting stations.

Winners are expected to be confirmed around midnight, although the results for closely contested constituencies could come out early Thursday morning.

Tentative turnout for this year's local elections was tallied at 50.9 percent, the second-lowest ever for local elections, as 22.5 million of 44.3 million eligible voters cast ballots, according to the National Election Comnission (NEC).

Despite registering a record early voting turnout of 20.62 percent, the final turnout came in far lower than the 60.2 percent logged in the 2018 local elections.

The PPP was looking to extend the momentum of the March 9 presidential election victory and help the new government to powerfully push its agenda from the start.

The conservative party believes Yoon's summit with U.S. President Joe Biden and recent North Korea provocations have helped make its case to voters, especially to those seeking the stabilized operation of the Yoon administration.

The DP, which controls a majority in the National Assembly, was looking to recover from the presidential election defeat and expand its power across the nation to keep the Yoon government in check.

The liberal party, which scored a landslide victory in the 2018 local elections, also hoped it can overcome a recent internal feud, which was sparked by the DP co-interim chief Park Ji-hyun's call for a sweeping reform of the party, and a sexual misconduct case involving one of its lawmakers.

In the run-up to Wednesday's elections, the PPP and the DP have been wrangling over various issues, from an extra budget bill to support pandemic-hit small merchants to a proposal of merging Seoul's Gimpo International Airport with Incheon International Airport.

Source: Yonhap News Agency