The precise timing of Japanese prime minister Shigeru Ishiba’s resignation announcement – on a Sunday evening – took many by surprise; but the countdown to his departure arguably began just weeks after he took office.

Having won the presidency of the Liberal Democratic party (LDP) – a formidable political force that has governed Japan for much of the past seven decades – Ishiba called a snap election in search of a public mandate after a major funding scandal, and to silence his opponents on the right of the party.

The gamble was a disaster for Ishiba, who had coveted the top job for much of his career, and a red flag for the once-impregnable LDP, then trying to haul its way out of the same “money politics” mire that came back to haunt it this weekend.

The LDP and its junior coalition partner, Komeito, lost their majority in the lower house, forcing the already embattled Ishiba to lead a minority government.

After Ishiba limped through months of soaring rice prices, the return of a tariff-happy Donald Trump and an emboldened North Korea, a second, potentially punishing time at the polls came into view.

And so it turned out. For the second time in less than a year, the LDP was stripped of its majority – this time in upper house elections held in July.

In dealing a double whammy to Ishida’s fledgling government, voters made it clear that his party still had much to do to address the funding scandal – in which dozens of LDP lawmakers were found to have siphoned unreported profits from the sale of tickets to party gatherings into slush funds.

Ishiba’s predecessor, Fumio Kishida, apologised in February last year for “inviting suspicion and mistrust” in politics in the wake of the scandal, and promised to stop holding fundraising parties during his time as prime minister. But there has been no concerted show of contrition; Ishiba himself was forced to issue an apology after he gave gift certificates, paid for with his own money, to 15 newly elected LDP members of the lower house – a gesture his critics said was proof of a prevailing culture of monetary rewards in the party.

As the Mainichi Shimbun newspaper put it in an editorial days before the upper house poll, lawmakers had “underestimated” the strength of public anger over money in politics.

Ishiba claimed to have made “considerable progress” in addressing the scandal with the abolition of “policy activity expenses,” which do not have to be disclosed, but he and other LDP lawmakers opposed bans on corporate and group donations to party branches.

The fact that most of the dozens of politicians and their aides involved in the scandal were never indicted only added to the anger felt by many voters. “There is no sign of self-reflection on the significant loss of trust in politics,” the Mainichi said.

And so on Sunday, the same scandal that had felled his predecessor, Kishida, also brought Ishiba’s premiership to an abrupt end.

The LDP has been here before, however – and recovered.

In the mid-1990s it reached an improbable accommodation with the socialists, whose leader, Tomiichi Murayama, was installed as prime minister in return for their participation in a three-party coalition. In 2009, the LDP was punished a second time following a slew of scandals that saw it relinquish power to the opposition for the first time since the war.

As it braces for a leadership election in early October, the LDP on Monday began its search for a successor with the ability to repeat those feats of resurrection.

“Having watched the party’s fault lines widen over the past year … party leaders may look for a leader who can promote unity, generate public excitement and support, and work with one or more opposition parties to stabilise the government,” said Tobias Harris, founder of the political risk advisory firm Japan Foresight.

The focus on turning around the party’s fortunes could drown out debate on economic and foreign policy, despite concern over rising regional tensions, Trump’s trade war and the cost of living crisis.

They “may be less significant as the LDP grapples with an existential crisis that may well still result in the party going into opposition for the third time in its history,” Harris added.

Last autumn, after Ishiba presided over the LDP’s chastening lower house election results barely a month into his prime ministership, he conceded that voters had issued a “severe judgment” on his party – a phrase he repeated after July’s upper house debacle.

But unless the party’s warring factions can quickly regroup – possibly by coalescing around the youthful and media-friendly frontrunner Shinjiro Koizumi – the harshest verdict may be yet to come.