* Moon seen winning with 41.4% of votes
* New president faces challenges over North Korea, China
* Moon will have to seek cooperation in fractured parliament

Liberal politician Moon Jae-in won South Korea's presidential election on Tuesday, an exit poll showed, an expected victory that would end nearly a decade of conservative rule and bring a more conciliatory approach toward North Korea.
A decisive win for Moon would end months of political turmoil that led to parliament's impeachment of conservative former President Park Geun-hye over an extensive corruption scandal.
The Constitutional Court upheld the impeachment in March, making Park the first democratically elected leader in South Korea to be removed from office and triggering a snap election to choose her successor.
Wearing a dark blue suit and blue tie, Moon was seen shaking hands with supporters and party officials and smiling on his way to a meeting of his Democratic Party after the exit poll results were announced.
"We will need to calmly wait and see as this was just exit polls," he told party members. "But if things go on this way and we win, today’s victory is thanks to sheer desperation of the people who wanted a regime change."
"We will accomplish the two tasks given to us, reform and national unity that the people of this country desire."
The exit poll by South Korea's three biggest broadcasters showed Moon, 64, capturing 41.4% of the votes in a field of 13 candidates. Official results were expected in the wee hours of Wednesday morning.
Former prosecutor Hong Joon-pyo was second with 23.3% of the votes and centrist candidate Ahn Cheol-soo had 21.1%. Definitive official results were expected early on Wednesday. A plurality is enough for victory.
"If exit polls are true, I will accept the results and just be satisfied with the fact that the Liberty Korea Party will be restored,” a downbeat-looking Hong told members of his conservative party.
Ahn said he would "humbly accept" the result.
Moon is expected to be sworn in for a five-year term later on Wednesday. He has said he would skip a lavish inauguration ceremony and start work straight away.
He is likely to quickly name a prime minister, who will need parliamentary approval, and the main cabinet positions, including national security and finance ministers, which do not need parliamentary confirmation.
Moon, who narrowly lost to Park in the last presidential election in 2012, favours dialogue with North Korea to ease rising tension over its accelerating nuclear and missile programme. He also wants to reform powerful family-run conglomerates, such as Samsung and Hyundai, and boost fiscal spending to create jobs.