The presidential nominees of both the ruling and opposition camps are targeting young voters, aware that lack of support from this demographic presents major challenges for their campaigns.

So far neither candidate has gained wide support from voters in their 20s and 30s. Former Prosecutor General Yoon Seok-youl, presidential nominee for the main opposition People Power Party, is forming his campaign team with that objective in mind.

"As supporters have vouched for different candidates during the presidential primary, some (of the party members) are contemplating leaving the party in disappointment at the primary results," People Power Party Chairman Lee Jun-seok told reporters Saturday.

After Yoon was picked as the party’s presidential nominee, some of its younger members, mainly those who supported Rep. Hong Joon-pyo, have been discussing whether to cancel their party membership.

They say Hong lost because Yoon received overwhelming support from party members in their 50s and older, and that Yoon’s win has dashed their hopes of reforming the conservative bloc.

"But we are certain that candidate Yoon can brush off the concern if he looks to understand and put efforts on what the younger generation wants in the future," Chairman Lee added.

"From meeting candidate Yoon several times recently, I felt that his political perspective definitely has appeal to younger generations as well."

On Thursday, a day before the People Power Party announced its primary results, a poll showed that 34 percent of voters in their 20s supported Hong as the party's presidential nominee for the main opposition party. Yoon got merely 6 percent support from the same group.

Yoon said Monday that he will discuss strategies with the party to widen his appeal to young voters, calling them critical "political assets" to the party.

"If this was a matter to be resolved quickly, such disappointing results would not have happened," Yoon said Monday, referring to the exodus of young party members after the primary results were announced.

"There are a lot more in the party who are knowledgeable about this matter, so I will prepare measures to make up for this problem."

Yoon and his party are at the moment working to decide who will serve in what roles in his presidential campaign. He has mentioned that he will work to involve high-ranking officials and traditional heavyweights from the party.

Gaining support from young voters is also a key task for former Gyeonggi Province Gov. Lee Jae-myung, the presidential nominee for the ruling Democratic Party. Polls have indicated that voters in their 40s and 50s are Lee Jae-myung’s main support base.

As he and his party already entered full "election mode" last week, launching the largest-ever election committee in the Democratic Party’s history, Lee Jae-myung has been spending much of his time meeting with young voters and making promises in response to their concerns.

He has emphasized expanding state-run welfare programs with additions such as universal basic income, which would mainly affect young voters concerned about unemployment and lack of opportunities to advance their careers after college.

"If populism is needed to save youth devoid of hope, I will gladly do whatever it takes, even if that requires populism," Lee Jae-myung said in a Facebook post Sunday while sharing a story about a 22-year-old man who took his own life due to the financial struggle of caring for his incapacitated father.

Lee Jae-myung has put forth a vision to supply large quantities of long-term public rental homes as an affordable housing option, mainly for young voters who have lost hope of buying their own homes due to skyrocketing housing prices.

The candidate also publicly apologized for the Moon Jae-in administration’s failure to stabilize housing prices.

"I am preparing a large-scale public housing supply project that is unimaginable to our common senses," Lee Jae-myung said at a meeting with young voters Saturday. "Younger generations, the most vulnerable group of people in our society, will be prioritized in supplying these homes."

The Democratic Party is also reviewing a campaign promise to bring in a new military conscription system. Under the tentative plan, the military would cut the mandatory service term to a year and would hire more professional soldiers, who would serve for three years.