Will the Democratic Party of Korea (DP) win the most seats in South Korea’s 2026 parliamentary by-elections?

At least four South Korean parliamentary seats will be contested in by-elections on June 3, 2026, held alongside the nationwide local elections taking place on the same day. Re-elections are equivalent to by-elections for the purposes of this market. This market will resolve to the party that wins the greatest number of National Assembly seats in the parliamentary by-elections scheduled for June 3, 2026. Any seat won in these elections will count, regardless of the party that controlled the relevant seat prior to these elections. Seats uncontested during the June 3 election will not have any impact on the resolution of this market. If the results of these elections are not known by December 31, 2026, 11:59 PM ET, this market will resolve to “Other”. This market’s resolution will be based solely on the number of seats won by the specified parties in these elections, not any coalition or alliance of which they may be a part. In the event of a tie between multiple parties for the most seats won, this market will resolve in favor of the party that received a greater number of valid votes across all the relevant parliamentary by-elections. In the event that results in a tie, this market will resolve in favor of the party whose listed full name appears first in alphabetical order. This market will resolve based on the results of the elections as indicated by a consensus of credible reporting. If there is ambiguity, this market will resolve based solely on the official results as reported by the South Korean government, specifically the National Election Commission. Note: this market includes any National Assembly seats contested in by-elections scheduled for June 3, 2026, not just elections which are scheduled as of this market’s creation.

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