Sunday's Tokyo Metropolitan Assembly election dealt a hard blow to Prime Minister Shinzo Abe, with his Liberal Democratic Party suffering a historic defeat and securing only 23 seats — the lowest-ever figure for the LDP.

But another big loser in the election may face problems more serious than those weighing on Abe. Despite being the largest opposition party in the Diet, the Democratic Party won just 5 of 127 seats in the assembly.

The bleak result has underlined how few voters regard the DP as an alternative political force that could replace the ruling LDP.