Prime Minister Sanae Takaichi¡¯s Liberal Democratic Party secured a historic landslide victory in Sunday¡¯s Lower House election with NHK projections showing the party securing a two-thirds supermajority in the 465-seat Lower House by itself.

Results early Monday showed that the LDP, which had 198 seats before the election, had won 316 seats, giving it a higher proportion of representatives in the Lower House than any other party in postwar Japan.

Together with its coalition partner, the Japan Innovation Party (JIP), the bloc had won 352 seats, significantly expanding its majority of 233.

This will essentially allow the LDP-led coalition to override challenges that emerge as a result of its lack of a majority in the Upper House. In the event key bills and budgets are voted down in the Upper House, they can be overridden in the Lower House with a two-thirds majority.

The opposition Central Reform Alliance (CRA), formed by the Constitutional Democratic Party of Japan (CDP) and Komeito just before the election, meanwhile, saw its preelection seats drastically reduced ¡ª to just 49 seats. The defeat could lead party co-leader Yoshihiko Noda, who has put his political career on the line for the new party, to resign.

The outcome was reminiscent of a 2012 election, when the LDP ¡ª after a disastrous 2009 poll in which it lost power ¡ª regained its control of the Lower House by winning 294 seats. That victory served as the launchpad of former Prime Minister Shinzo Abe¡¯s almost eight-year rule over Japan. The LDP¡¯s previous best past performance in a Lower House election bad been in 1986 ¡ª when the Upper House election was held simultaneously ¡ª during which it secured 300 seats under then-President Yasuhiro Nakasone.

Having all but secured a resounding mandate from the public, Takaichi said in a TV program Sunday night that she plans to further cement her party¡¯s relationship with the JIP.

¡°We drafted a joint policy agreement line by line with the JIP, with whom we shared a similar view of the nation, when we were cornered after Komeito left the coalition,¡± the LDP president said.

While urging the JIP to have a presence in her Cabinet, Takaichi also extended an open invitation to other parties.

¡°If other parties want to work with us, I¡¯d like to welcome them with open arms,¡± she said.

The ruling coalition¡¯s overwhelming victory far exceeds the 261-seat supermajority threshold that would give the LDP and the JIP an upper hand when passing key bills. With that minimum number of seats, the coalition will get to chair all 17 standing committees in the Lower House.

It¡¯s control of at least 290 seats also allows the coalition¡¯s lawmakers to...