South Korea's liberal presidential candidates on Wednesday called for extending the voting hours for the Dec. 19 election day so more people can cast their ballots to pick the country's new leader.

The main opposition Democratic United Party (DUP) had forwarded a revision bill that would allow people to vote from 6 a.m. to 9 p.m., compared to the present closing time for polls set at 6 p.m.

In a comment made on his Twitter account, DUP's presidential hopeful Moon Jae-in said it would be for the best if the voting hours were extended so people can more easily express their position on who is best qualified to run the country.

He pointed out that under the existing rules many irregular workers who have to work long hours cannot vote. He added that there are many countries in the world who keep polling booths open until 8 p.m. or even 10 p.m.

"If there is a need for change it should be changed and I can't understand why the ruling Saenuri Party is opposed to the plan," he said.

The spokesman's office for independent presidential candidate Ahn Cheol-soo also said on its official Facebook page that extending the polling hours could allow more people to vote. Ahn, founder of AhnLab, South Korea's largest anti-virus software firm, is a leading contender to win the country's top elected office.

"Many people have to work on election day even if it has been designated as a temporary holiday," it said, pointing out that extending the voting hours is natural.

The office, in addition, asked people to take part in an online petition calling for the extension of voting hours.

The move by the two candidates, however, has been challenged by Saenuri, which made clear that extending voting time will incur considerable extra costs and burden those charged with overseeing the election process.

Political pundits, meanwhile, said Moon and Ahn, who generally enjoy stronger support among young people, believe that extending the voting hours will allow them to win more votes. On the other hand, Saenuri's hopeful Park Geun-hye's election camp thinks such a move would be disadvantageous to the 60-year-old five term lawmaker's chances of winning the election.

Park has a strong following among conservatives and the older generation who generally have a higher turnout than young people.

The older generation also tends to vote early in the day. Since Saenuri controls close to half of all seats in the 300-member National Assembly, it is unlikely that the voting hours will be changed this time around. (Yonhap)