Former Prime Minister Lee Hae-chan has been elected the new chairman of the main opposition Democratic United Party. The six-term lawmaker won a dramatic come-from-behind victory over Rep. Kim Han-gil on Saturday, the final day of the party’s leadership race that began on May 20.

The new leader’s primary task is to manage the selection of a party candidate for the presidential election in December. The job sounds simple but is in fact complex because the party, after nominating its own presidential candidate, will probably look to hold a candidacy runoff with Ahn Cheol-soo, the frontrunner among liberal presidential hopefuls who is expected to announce his independent candidacy soon.

In a statement issued upon his election, Lee said he would try to make the party’s candidate nomination process an energetic “national festival” by ensuring that people from all walks of society participate in it.

Yet he needs to make the nomination process fair and transparent in the first place. For this, he has to wipe out the suspicions that he is closely associated with Moon Jae-in, the party’s leading presidential aspirant who served as President Roh Moo-hyun’s chief-of-staff.

In April, allegations surfaced in the DUP that Lee had formed a secret power-sharing alliance with Moon and Rep. Park Jie-won. Under the scenario, the three would share the leadership roles ― Moon as the party’s presidential candidate, Lee as party chairman, and Park as floor leader. Park’s election as new floor leader in May hardened the suspicions of collusion among the trio.

In the contest for the party chairmanship, Lee’s alleged alliance with Moon and Park militated against him. Lee denied any special ties with the two but many party delegates turned against him in disapproval of the trio’s alleged attempt to monopolize power.

In the coming candidate nomination process, Lee will have to behave carefully to avoid any unnecessary misunderstandings among presidential hopefuls.

A tough-talking politician, he will also have to update his views on North Korea. Lee recently called the ruling Saenuri Party’s bill on North Korean human rights a “diplomatic discourtesy,” arguing that the South should not attempt to intervene in the human rights situation in the North.

Yet the party’s presidential candidates contradicted Lee. For instance, Moon said during a recent visit to an Army troop that “the South should endeavor to enhance the human rights of North Koreans because human rights issues go beyond ideology.” Noting that human rights should be respected in any country, he called on Pyongyang to better protect its people’s basic rights.

Sohn Hak-kyu, another DUP presidential runner, also said that “the South should say what it must say about the North’s human rights.” He pointed out that “the North cannot be seen as a normal state as it spends money on nuclear weapons development while its people starve to death.”

If Lee sticks to his outdated views on North Korea, he could put the presidential candidates in an embarrassing situation. Furthermore, it would undermine voter support for the DUP as a large majority of the public now believes that political parties should openly criticize the North for its human rights violations and other anachronistic behavior.

Known as a politician with a short fuse, Lee also needs to take care not to lose his temper in public. Recently, he drew fire by abruptly hanging up the phone during a telephone interview with a radio station. He did this nonsensical act when the host asked him questions about DUP Rep. Lim Soo-kyung, who recently insulted North Korean defectors by calling them “traitors.”

As DUP chairman, Lee’s mission goes beyond smooth management of the nomination process. He vowed to do all he could to win the December election. Yet no DUP candidate currently enjoys a popularity rating as high as that of Rep. Park Geun-hye of the Saenuri Party.

One reason may be low voter confidence in the party’s ability or readiness to govern the nation. An insightful election strategist with ample experience, Lee probably knows this better than anyone else. Hence his first order of the day should be to make the DUP a more responsible and trustworthy political party.