Seoul, Jun 2 (AP) Millions of South Koreans are voting Tuesday for a new president in a snap election triggered by the ouster of Yoon Suk Yeol, a conservative who now faces an explosive trial on rebellion charges over his short-lived imposition of martial law in December.

Pre-election surveys suggested Yoon's liberal archrival, Lee Jae-myung, appeared headed for an easy win, riding on deep public frustration over the conservatives in the wake of Yoon's martial law debacle.

The main conservative candidate, Kim Moon Soo, has struggled to win over moderate, swing voters as his People Power Party remains in a quagmire of internal feuding over how to view Yoon's actions.

This election serves as another defining moment in the country's resilient democracy, but observers worry a domestic divide worsened by Yoon is far from over and could pose a big political burden on the new president.

The past six months saw large crowds of people rallying in the streets to either denounce or support Yoon, while a leadership vacuum caused by Yoon's impeachment and ensuing formal dismissal rattled the country's high-level diplomatic activities and financial markets.

The winning candidate will immediately be sworn in as president Wednesday for a single, full term of five years without the typical two-month transition period. The new president will face major challenges, including a slowing economy, President Donald Trump's America-first policies and North Korea's evolving nuclear threats.

The election commission says voting began at 6 am (GMT +0900 hrs) at 14,295 polling stations nationwide that will close at 8 pm. Observers say the winner could emerge as early as midnight.

Lee, whose Democratic Party led the legislative effort to oust Yoon, has emerged as the clear frontrunner in opinion surveys released in recent weeks.

More than 15 million people already have cast ballots during a two-day early voting period last week, accounting for nearly 35% of the country's 44.4 million eligible voters.

Final pitches made by rival candidates In his final campaign speeches Monday, Lee promised to revitalise the economy, reduce inequality and ease national divisions. He urged the people to vote for him, arguing that a win by Kim would allow Yoon's "rebellion forces" to return.

"If they somehow win, that would mean the return of the rebellion forces, the destruction of democracy, the deprival of people's human rights, the normalisation of martial law and our country's downfall into a backward, third-world nation," Lee told the crowd gathered at a Seoul park.

Kim, a former labour minister under Yoon, warned that a Lee win would allow him to wield excessive power, launch political retaliation against opponents and legislate laws to protect him from various legal troubles, as his party already controls parliament.

Lee "is now trying to seize all power in South Korea and establish a Hitler-like dictatorship," Kim told a rally in the southeastern city of Busan.

Lee's positions would impact nation's direction Lee, who led the opposition-led campaign to oust Yoon, has been a highly divisive figure in South Korean politics for years.

As a former child labourer known for his inspirational rags-to-riches story, Lee came to fame through biting criticism of the country's conservative establishment and calls to build a more assertive South Korea in foreign policy. That rhetoric has given him an image as someone who can institute sweeping reforms and fix the country's deep-seated economic inequality and corruption.

His critics view him as a dangerous populist who relies on political division and backpedals on promises too easily.

On foreign policy, Lee has not made any contentious remarks recently and has steadfastly vowed to pursue pragmatic diplomacy. He has called South Korea's alliance with the US the foundation of its foreign policy and promised to solidify a trilateral Seoul-Washington-Tokyo partnership, a stance that is not much different than the position held by South Korea's conservatives.

Experts say there aren't many diplomatic options for South Korea as it tries to address Trump's tariff hikes and calls for South Korea to pay more for the cost of the US military presence, as well as North Korea's headlong pursuit of nuclear weapons. Experts say that has made both Lee and Kim avoid unveiling ambitious foreign policy goals.

Lee's government still could become engaged in "a little bit of friction" with the Trump administration, while Kim's government, which prioritises relations with Washington, will likely offer more concessions to the US, said Chung Jin-young, a former dean of the Graduate School of Pan-Pacific International Studies at South Korea's Kyung Hee University.

Chung predicted Lee won't be able to pursue overly drastic steps on foreign policy and security, given the country's foreign exchange and financial markets are very vulnerable to such changes.

Lee has preached patience over Trump's tariff policy, arguing it would be a mistake to rush negotiations in pursuit of an early agreement with Washington. Kim has said he would meet Trump as soon as possible.

On Monday, South Korean trade officials held an emergency meeting to discuss a response to Trump's announcement that the US will raise tariffs on steel and aluminium products to 50% beginning June 4.

South Korea's central bank last week sharply lowered its 2025 growth outlook to 0.8%, citing the potential impact of Trump's tariff hikes and weak domestic demand worsened by the political turmoil of past months.

Prospects for improved North Korea relations are unclear Relations with North Korea remain badly strained since 2019, with the North focused on expanding its nuclear arsenal while refusing dialogues with South Korea and the US.

Since his second term began in January, Trump has repeatedly expressed his intent to resume diplomacy with North Korean leader Kim Jong Un, but Kim has so far ignored the offer while making Russia his priority in foreign policy.

Lee, who wants warmer ties with North Korea, recently acknowledged it would be "very difficult" to realise a summit with Kim Jong Un anytime soon. Lee said he would support Trump's push to restart talks with Kim Jong Un, which he believed would eventually allow South Korea to be involved in some projects in North Korea.

Foreign policy strategists for Lee understand there isn't much South Korea can do to bring about a denuclearisation of North Korea, said Paik Wooyeal, a professor at Seoul's Yonsei University.

He said Lee also doesn't share the Korean nationalistic zeal held by ex-liberal President Moon Jae-in, who met Kim Jong Un three times during his 2017-22 term. (AP) AMJ AMJ