TOKYO, July 22 (Xinhua) -- Japan's ruling bloc led by Prime Minister Shinzo Abe won more than half of the contested seats in Sunday's upper house election, maintaining a majority in the chamber.

However, the ruling parties and others who advocate constitutional reform did not win the needed 85 seats to get a two-thirds majority, a prerequisite for any amendment.

With 370 candidates vying for the 124 seats, 74 are chosen in specific districts and 50 through proportional representation.

As of 03:30 local time Monday, the ruling Liberal Democratic Party and its coalition partner Komeito won 69 out of the 124 seats up for grabs. Holding 70 of the seats in the uncontested half, they crossed the victory line set by Abe to maintain a majority in the 245-seat chamber.

Members of the upper house serve six-year terms, with about half the seats up for grabs every three years. Due to electoral reform, the number of seats in the upper house will increase by six to 248 in 2022. Of the six, three were added this time to bring the total seats to 245.