A newly expanded Constitutional Democratic Party of Japan was formally launched Tuesday with 150 Diet members, making it the nation’s largest opposition party amid continuing speculation a snap general election could be held within weeks.

But the party faces challenges in convincing the public it’s more than simply an updated version of the old Democratic Party of Japan, which held power between 2009 and 2012 before losing popularity and being ousted by the Liberal Democratic Party and Komeito coalition. The center-left CDP’s leader, Yukio Edano, and its four top officials are all former members of the DPJ.

In his remarks to the new party, Edano said it was now time to challenge the ruling LDP-Komeito coalition in an extraordinary Diet session, to be convened in the fall, on everything from past scandals involving outgoing Prime Minister Shinzo Abe to the government’s controversial decisions to spend public money on face masks earlier this year in response to the novel coronavirus.