Gyeonggi Province is the No. 1 in population size and number of voters, surpassing those of the nation’s capital Seoul. Together with the neighboring Incheon -- Korea’s third-largest city -- the region accounts for nearly 30 percent of total voters, or 12.67 million of the 42.47 million eligible voters registered nationwide.

A recent survey by Gallup Korea, released Friday, showed that a large proportion of the voters in this region are still undecided over which way to vote on May 9 or during the early voting period from Thursday to Friday.

According to the pollster, 39 percent of the respondents residing in the Incheon-Gyeonggi area said they might choose who to support as events unfold in the lead-up to the election.

The Incheon-Gyeonggi area marked the highest proportion of swing voters, followed by Seoul with 32 percent, Daegu-North Gyeongsang Province with 32 percent and Busan-South Gyeongsang Province with 31 percent.

Only 21 percent of the respondents in the Daejeon-Chungcheong provinces and 26 percent of those in the Gwangju-Jeolla provinces said they might change their support. The nationwide average was 32 percent.

Gallup Korea also reported that the proportion of swing voters was high among those who identified themselves as centrists. About 37 percent of the centrist respondents said they might change their minds, while 33 percent of conservatives and 30 percent of liberals might do so.

Based on the candidates they are supporting, 60 percent of the supporters of conservative Yoo Seong-min said they have yet to decide who they will vote for, followed by 48 percent of those supporting progressive Sim Sang-jeung and 38 percent of centrist Ahn Cheol-soo’s supporters.

The proportion of swing voters was low among those supporting liberal Moon Jae-in (26 percent) and conservative Hong Joon-pyo (23 percent).

By job or status, 58 percent of college students said they might change their minds, followed by white-collar workers with 37 percent and self-employed respondents with 30 percent. The proportion was relatively low among housewives and those unemployed.

Similar to past polls, those aged between 19 and 39 replied that they were undecided, along with 55 percent of those in their 20s and 38 percent of those in their 30s.

Early voting is scheduled to start this Thursday for a two-day run.

Some political watchers predicted that early votes may make up around 20-25 percent of total ballots in this year’s election.

By Kim Yon-se (kys@heraldcorp.com)