The ruling LDP won 63 seats, more than half of the 125 seats up for grabs in the poll. As its junior partner Komeito Party secured 13 seats, the ruling camp grabbed a combined 76 seats, comfortably retaining a majority in the 248-member upper chamber of parliament, or more than two-thirds majority needed for constitutional revision.

The main opposition Constitutional Democratic Party of Japan won 17 seats, down from 23 contested seats. The election took place two days after former Prime Minister Shinzo Abe was shot dead during a stump speech Friday.

The final voter turnout was 52.05 percent, higher than 48.8 percent in the previous 2019 election for upper house, the Ministry of Internal Affairs and Communications said Monday.

In Sunday's poll, 125 of the seats in 248-member Upper House came up for grabs, with 545 candidates vying for the seats at stake, including 74 from single-seat districts, 50 through proportional representation, and the one from vacant seat.

Elections are held for half of the Upper House seats every three years. The key issues in the race included Kishida's COVID-19 response, soaring prices in the wake of Russia's military operation in Ukraine and security policy issues including defense spending.

Kishida, who took office last October, pledged Sunday night to move politics forward with "a huge sense of responsibility." "The projections suggested great results for the ruling coalition and his LDP. But I heard harsh opinions during the campaign period and will take them on board," the premier told public broadcaster NHK.

Kishida also said he believes that many people are greatly concerned about surging prices and want their political leaders to address the issue. On possible Constitutional amendments, Kishida said he will focus on efforts to formulate draft revisions that can be put to a national referendum.

"I will seek to deepen parliament debates on the Constitution and gain the public's understanding," he said. — Agencies