Explainer-South Korea's election: polls, key issues and how it works

South Korea will hold legislative elections on Wednesday to decide the make-up of its 300-strong National Assembly, with most polls suggesting an outcome that will do little to break the deadlock that has gripped the divided government.

WHY DOES THE ELECTION MATTER?

The election comes nearly two years after conservative President Yoon Suk Yeol won the 2022 presidential election defeating Lee Jae-myung of the Democratic Party by 0.73% - the slimmest margin in South Korean history. 

South Korea has a powerful presidential system, checked and balanced by the assembly which can pass or stop bills.

Yoon has a separate five-year term and is not up for election this time, but the vote is seen as a referendum on the president and his bitter rival Lee.

Yoon has suffered from low approval ratings for months and will further lose momentum if his People Power Party (PPP) performs poorly in the election. The parliament is currently dominated by the DP which holds 142 out of 297 seats, and allies with smaller opposition parties to hold the majority.

"With the opposition-led parliament, it has been hard to make a policy push or achievement over the last two years. Without change during the rest of his term, it would be extremely hard to do his job," said Lee Jun-han, professor of political science at Incheon National University. 

Early voting on two days last week reached a turnout of 31.28%, a record high for a legislative election, the National Election Commission said.

According to a poll conducted by KBS and Hankook Research between March 30 and April 2, four in 10 respondents said they would vote for the DP, while 33% said they would back PPP.

In a joint survey released on Thursday by four pollsters, however, 39% of respondents said they would vote for the PPP and 37% for the DP.

The two major parties have said dozens of regions are too close to call and new polls are prohibited in South Korea in the last six days before the election.

If the opposition wins 200 seats or more, there is a risk Yoon could face impeachment and some PPP members have made this point to appeal to voters.

"Please save the president's veto power to stop the opposition's parliamentary dictatorship at the least," the PPP's floor leader Yun Jae-ok said in a meeting on Monday.  

WHAT ARE THE KEY ISSUES?

In recent polls, the cost of living and high food inflation have emerged as key issues among voters. The price tag of green onions has made headlines after Yoon's visit to a supermarket. Another issue is the prolonged walkout by trainee doctors and some senior doctors.

Polls initially showed strong public support for the government which plans to increase medical school admissions by 2,000 starting in 2025, a plan opposed by the protesters.

Last week, Yoon showed the first signs of flexibility in his medical reform plan, however, as some voters have started to blame him for appearing reluctant to seek a compromise.

Political parties have also vowed to tackle the fertility crisis with measures such as public housing and tax breaks. South Korea has the world's lowest fertility rate, or the average number of children born to a woman, and data shows it is likely to fall to 0.68 in 2024, past the figure of 0.78 in 2022, which was already a record low.

Analysts expect the government's corporate reform push, dubbed the "Corporate Value-up Programme", to continue regardless of the election turnout as both parties support the plan to boost the stock market. The Yoon administration's plan to abolish capital gains taxes, which requires parliamentary approval, remains an issue the DP could oppose.

Corruption remains a major issue. Likely flashpoints are the ambassador to Australia who resigned last month amid controversy over his appointment while being under a corruption investigation, and the First Lady's "Dior bag scandal". Main opposition leader Lee is facing trials over charges including bribery which will see him appear in court during the election cycle.

Analysts said Seoul's foreign policy, which has sought closer ties with Washington and Tokyo under Yoon, will not change significantly whoever wins. South Korea's powerful presidency leaves little room for parliament to weigh in on the president's foreign policy agenda.

HOW DOES THE ELECTION SYSTEM WORK?

South Korea has a partly proportional representation system for its legislative elections which means voters will cast one ballot for district representatives, who have 254 seats in the parliament. They will also vote for a political party which will decide the share of the 46 proportional representation seats.

The rise of third parties in recent polls has come as a surprise in the fourth-largest economy in Asia where politics is often dominated by the two major parties.

More than 20% of voters said they would vote for a third party launched by former justice minister Cho Kuk via the proportional representation vote, according to a Gallup poll published on March 29. Cho is also facing jail time in a fraud case.