(dpa) - South Korea's conservative Grand National Party (GNP) was poised to replace the liberal United Democratic Party (UDP) as the largest party in parliament in Wednesday's general election, according to the most recent opinion polls.
President Lee Myung Bak of the GNP was elected in February, ending 10 years of Liberal domination in the East Asian country.
Some 38 million South Koreans are eligible to vote for 299 members of the National Assembly.
On Tuesday, the parties were busy trying to persuade the undecided, who are estimated to account for 20 per cent of voters.
Pollsters say that, owing to voter apathy, they expect turnout to be even lower than the last election four years ago when 60.6 per cent of eligible voters went to the polls.
To encourage people out to polling stations, voters were expected to receive vouchers for reduced-price entry to museums and public buildings.
"What can be more important than casting a ballot for you and the country's future?" the head of the national election commission, Ko Hyun Chul, said on Korean television.
The chances that the GNP could achieve a two-thirds majority in parliament have faded after an internal squabble over candidate nominations tarnished the party's image.
The GNP is expected to win 160 of the 299 seats in parliament, against 100 for the UDP.
South Korea's presidential system of government allows the president to stay in power even if parliament is dominated by the opposition.
The GNP called on voters to elect a "stable" government, while the UDP said they should keep the government in check.
Recent tensions with North Korea are expected to have little impact on the election.
Pyongyang has recently threatened to cut off dialogue with Seoul after the new government in South Korea adopted a tougher stance with its communist neighbour.