Liberals are preparing for a Friday the 13th partyroom showdown, with Angus Taylor set to challenge Opposition Leader Sussan Ley after a slew of high-profile resignations.
Supporters of the leadership rivals spent Thursday working the phones and walking the halls of parliament in a last-ditch effort to canvass for votes, while Labor MPs launched jibes at their opposition counterparts for the open display of disunity.
After Mr Taylor quit the front bench on Wednesday night, nine of Mr Taylor's supporters followed him in abandoning the shadow ministry on Thursday, declaring they no longer had confidence in Ms Ley's leadership.
Energy spokesman Dan Tehan tendered his resignation and said he would nominate for the deputy leadership when the party convenes on Friday at 9am.
Conservative senators Michaelia Cash, James Paterson and Jonno Duniam were among other senior Liberals to quit, joined by Claire Chandler, Matt O'Sullivan and Phil Thompson.
Queensland senator James McGrath, previously a supporter of Ms Ley, also resigned.
The ongoing leadership speculation needed to be brought to a head, Senator Cash said.
"I will be voting for a spill of the leadership when the party room next meets," she said in a brief statement.
Senator Paterson said Ms Ley's leadership was untenable because a number of opinion polls have showed the Liberals tanking to historic lows, overtaken by anti-immigration minor party One Nation.
"This cannot go on. If it goes on, there will be nothing left of the Liberal Party at the next election," Senator Paterson told reporters after tendering his resignation.
Senator Duniam said internal party bickering needed to end so the opposition could unite and focus on holding the Labor government to account.
Both senators accepted some personal responsibility for the Liberals' polling plunge.
A leadership ballot will take place during a special partyroom meeting on Friday morning.
The opposition leader maintained her silence as the resignations flowed in, only putting out a social media post outlining a plan for "a better future" by taking the pressure off families, fixing the budget and keeping Australians safe.
Government ministers used question time on Thursday to take pot-shots at their coalition counterparts, attacking Mr Taylor's record and lambasting the ongoing dysfunction.
"Julius Caesar had more support from his senators than what we've seen going on today," Education Minister Jason Clare told parliament.
Mr Taylor sat two rows back from the front bench and spent most of question time looking at his phone.
As MPs worked furiously to tally numbers, leading moderate Dave Sharma - who has been a strong supporter of Ms Ley - was spotted having separate conversations with two key conservatives.
Queensland senator Paul Scarr, also a backer of Ms Ley, said the decision to overthrow the party's first female leader less than a year into her term would be costly politically.
"I have absolutely no doubt that if Sussan loses tomorrow, the fact that the Liberal Party has replaced its first woman leader after less than 12 months will be weaponised brutally by our political opponents," he told reporters.
Conservatives argue the decision to roll Ms Ley is not a gendered one, and point to Labor knifing Australia's first female prime minister Julia Gillard in 2013.
Mr Thompson and fellow conservative Jess Collins officially petitioned Ms Ley on Thursday morning to call a partyroom meeting to decide the leadership.
A number of shadow ministers then tendered their resignations from the front bench to support Mr Taylor.
