For the first time in South Korea's democratic history, a ruling party has lost its majority status in the National Assembly while the country's President, who is affiliated to the party, is still in office.
The Saenuri Party's crushing defeat - not only losing its House majority but also securing one fewer seat than the main opposition Minjoo Party's 123 - has dealt a devastating blow to President Park Geun Hye and left her party in disarray.
Although the party will still be in power as the Cabinet is appointed by Ms Park, her weakened support base in Parliament means that she will have an even harder time pushing for reform Bills aimed at revitalising the sluggish economy and creating more jobs for young people - key campaign pledges that led to her election in 2012.
With her party barely maintaining a majority in the last Parliament, she was already facing gridlock and Wednesday's poor results mean even less can be done in the remaining 20 months of Ms Park's five-year term, rendering her a lame duck.
There is now talk that she might reshuffle the Cabinet in a bid to "show to the public her desire to better serve the people", according to the Yonhap news agency.
But winning over the people again will be an uphill task given the many problems she faces.
Not least of this is Ms Park's authoritarian leadership style and her confrontational approach towards the opposition.
Her authoritarian style has been cited as a key factor that turned voters off in these elections. This was evident in how she scolded officials in times of crisis, including the 2014 sinking of the Sewol ferry that killed 304 people and last year's Middle East respiratory syndrome (Mers) outbreak that left 36 dead. But what also irked the people was how she pushed ahead with the introduction of state-written history textbooks despite massive public protests.
To regain public support, analysts said, Ms Park will have to change her confrontational attitude towards the opposition and start communicating with the legislature and listening to people.
With Saenuri holding only 122 seats and the law requiring a three-fifth super majority, or 180 of the 300 votes, to pass Bills, her ability to gain the support of the opposition bloc is crucial.
However, as international relations professor Kim Jae Chun from Sogang University's Graduate School of International Studies pointed out, "she does not have that power of persuasion".
Another problem she faces in trying to avoid becoming a lame duck is that her Saenuri Party itself is in a shambles after key candidates, including former Seoul mayor Oh Se Hoon and former Gyeonggi governor Kim Moon Soo, were defeated by the opposition.
Party chairman Kim Moo Sung has offered to step down to take responsibility for the party's poor showing. At least two other party leaders have stepped down and more are expected to resign.
The party's supreme council convened an emergency meeting yesterday afternoon to discuss how to move forward and reform its leadership.
Beyond Ms Park's immediate problem of trying to have a functional government in the next 20 months is that of next year's presidential election.
Her party's poor result means that Saenuri may not have enough support for its candidate to win that election.
This, however, has thrown the presidential election wide open and the opposition parties are already thinking ahead to 2017's poll.
Mr Ahn Cheol Soo, who led the newly-formed minor opposition People's Party to win a surprisingly high number of 38 seats and become the third-largest party in the new Parliament, has been singled out as a potential candidate.
The former software tycoon, who left Minjoo to form his own party early this year, won voters over with promises that it would be an alternative voice for the people.
"Ahn is obviously the star of this election, leading the People's Party to an incredibly large gain," said Dr Kang Sei Miong, a senior research fellow at Sejong Institute. "He and his party are expected to exert greater power and capacity in the future."
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