Race looks set to go down to the wire: pollsters

The two rivals for the Republic of Korea's presidency made a final pitch to voters on Tuesday, on the eve of an election that looked set to go down to the wire and could produce the country's first female leader.

The winner of Wednesday's ballot will face numerous foreign and domestic challenges, including the Democratic People's Republic of Korea, a slowing economy and soaring welfare costs in one of the world's most rapidly aging societies.

Ruling conservative party candidate Park Geun-hye is looking to make history as the first female president and the first to be related to a former leader.

Park, 60, is the daughter of the late ruler Park Chung-hee, who was shot dead by his spy chief in 1979. Park's mother was killed five years earlier by a pro-DPRK gunman aiming for her father.

Standing between her and the presidential Blue House is the liberal Moon Jae-in, 59, from the main opposition party, a former human rights lawyer who was once jailed for protesting against the rule of Park's father.

Final opinion polls showed that Moon had eroded the small, but clear lead Park enjoyed for much of the campaign, leaving the result too close to call, said commentators.

After locking in the support of their respective conservative and liberal bases, the two candidates have actively wooed crucial centrist voters, resulting in significant policy overlap.

Both have talked of "economic democratization" - a campaign buzzword about reducing the social disparities caused by rapid economic growth - and promised to create new jobs and increase welfare spending.

Moon has been more aggressive in his proposals for reining in the power of the giant family-run conglomerates, or "chaebols", that dominate the ROK economy and there are significant differences on policies regarding the DPRK.