South Korea's National Election Commission said Sunday that a total of seven candidates have registered to run in the country’s presidential election, scheduled for June 3.

With two-day registration now closed, Lee Jae-myung of the main liberal Democratic Party of Korea — a clear frontrunner in the polls — was assigned the No. 1 spot on the ballot. He is followed by Kim Moon-soo of the conservative People Power Party at No. 2 and Lee Jun-seok of the minor New Reform Party at No. 4.

Candidate numbers are assigned based on the number of seats each party holds in the National Assembly, starting with the largest. The No. 3 slot was left vacant after the Rebuilding Korea Party chose not to field a candidate. Numbers 5 through 8 were given to two minor party candidates and two independents.

The official 22-day campaign period begins Monday.

This snap election was triggered by the removal from office of former President Yoon Suk Yeol in April, following his shocking declaration of martial law in December last year.

The race is shaping up to be a showdown between Lee Jae-myung and Kim, who represent the country’s rival liberal and conservative blocs, respectively. A poll released Sunday showed Lee Jae-myung leading with 52.1 percent support in a hypothetical three-way race against Kim and Lee Jun-seok. Kim received 31.1 percent, while Lee Jun-seok garnered 6.3 percent.