South Chungcheong Gov. An Hee-jung of the opposition Democratic Party narrowed his gap with front-runner Moon Jae-in, former head of the party, in terms of approval rating among presidential hopefuls this week, a poll showed Thursday.

An garnered an approval rating of 19.3 percent, up 2.6 percentage points on-week, narrowing the gap with Moon who posted 32.7 percent, down 0.2 point, the poll conducted by Realmeter showed.

Acting President and Prime Minister Hwang Kyo-ahn, who has been favored by the conservative bloc as a potential candidate after Former UN Secretary-General Ban Ki-moon dropped out of the race, posted 16.5 percent, up 1.2 points from a week earlier.

Rep. Ahn Cheol-soo from the People's Party got 8.6 percent, down 0.9 point, trailed by Seongnam Mayor Lee Jae-myung of the main opposition party with 7 percent and Rep. Yoo Seong-min from the Bareun Party with 3.9 percent.

By party, the Democratic Party posted an approval rating of 45 percent, beating the ruling Liberty Korea Party which climbed 1.7 points to 16.2 percent after changing its name from the Saenuri Party.

The survey was conducted on 1,515 voters from Monday to Wednesday with a margin of error of plus or minus 2.5 percentage points. (Yonhap)