Ruling party presidential candidate Lee Jae-myung is running neck and neck with his main opposition rival Yoon Suk-yeol at 34 percent support against Yoon's 33 percent, a poll showed Friday.

Lee of the liberal Democratic Party lost 3 percentage points from last week, while Yoon of the conservative People Power Party added 2 points, according to the Gallup Korea survey conducted on 1,002 adults from Tuesday to Thursday.

Ahn Cheol-soo, the presidential candidate of the minor opposition People's Party, maintained his record high 17 percent from last week, while Sim Sang-jeung of the minor progressive Justice Party followed at 3 percent.

Undecided voters came to 12 percent.

By age group, Lee was popular among voters in their 40s and 50s, earning 51 percent and 42 percent, respectively. Yoon performed well among voters in their 60s and aged 70 and older, scoring 43 percent and 49 percent, respectively.

Among those in their 20s, Yoon led with 30 percent, followed by Lee at 22 percent, Ahn at 17 percent and Sim at 8 percent.

When asked if their choice of candidate was based on their approval of them or disapproval of others, the respondents were split 48 percent to 46 percent, respectively.

Around 50 percent of voters 40 and older said their choice of candidate was based on approval, while around 60 percent of younger voters in their 20s and 30s said it was based on disapproval of the others.

President Moon Jae-in received an approval rating of 41 percent and a disapproval rating of 53 percent.

The survey had a margin of error of plus or minus 3.1 percentage points at a 95 percent confidence level. (Yonhap)

For more information regarding the survey results go to the National Election Survey Deliberation Commission homepage.