A bevy of Liberal frontbenchers supporting Angus Taylor’s leadership challenge resigned their positions on Thursday, ahead of Friday’s 9am party vote.

With momentum moving towards Taylor, his backers and those of Sussan Ley were working on the relatively small number of people whose votes were regarded as in play.

The Ley camp said she would not resign.

The concern for the Taylor camp was not the actual leadership vote, but to ensure support for the preceding vote to get a “spill” of the leadership. A few Liberals committed to voting for Taylor were more equivocal about voting for the spill motion.

The Taylor camp pointed out that if the spill were to fail, it would simply be put again when parliament was back in a fortnight. Meanwhile, frontbenchers who had quit would not go back into the shadow ministry, so the situation would be chaotic for Ley.

The resignations were spread over the day. They included:

• James Paterson (shadow minister for finance)

• Jonno Duniam (shadow minister for home affairs)

• Michaelia Cash (shadow foreign minister)

• Dan Tehan (shadow minister for energy and emissions reduction)

• James McGrath (shadow special minister of state)

• Matt O’Sullivan (shadow assistant minister for infrastructure)

• Phil Thompson (shadow assistant minister for the NDIS and defence)

• Claire Chandler (shadow minister for cyber security and science)

• Leah Blyth (shadow assistant minister for stronger families and stronger communities)

• Dean Smith (shadow assistant minister for energy, emissions Reduction, foreign affairs and trade).

The resignations of McGrath and Smith were particular blows for Ley, because they had been her supporters.

Paterson, a conservative factional chief, said the polls showed votes had been lost at a rate of more than 200,000 a month. If this went on “there’ll be nothing left of the Liberal Party by the next election”.

Paterson described Taylor as “the smartest policy brain in the shadow cabinet. He is a man of deep conviction and courage and values.”

“Angus understands that this is a change or die moment for the Liberal Party. We must change or we will not continue to exist,” Paterson said.

Taylor issued a video in which he said “I believe we need strong and decisive leadership that gives Australians clarity, courage, and confidence in providing a vision for the future”.

Ley put out multiple social media posts.

The position of deputy leader is being keenly contested, with the present deputy, Ted O'Brien, coming under challenge from Tehan and Senator Jane Hume, a backbencher who was finance spokeswoman last term. The deputy leader gets to choose their own portfolio.

If Hume won, she would be the first deputy to be in the Senate since Fred Chaney, who was deputy under Andrew Peacock in 1989-90.

Fellow Victorian senator Sarah Henderson said Hume “is a magnificent woman. She is very experienced. Of course she is a Victorian senator. She has been a great advocate for our party and for our country. She has a wonderful track record and I do think that we need to promote a senior woman.”

Cash said: “Following the events of recent days I believe the matter of the Liberal Party Leadership needs to be brought to a head.”

She said she was not resigning as Leader of the Opposition in the Senate, “a role bestowed upon me by the Senate party room”.

In his resignation statement Duniam said, “I have consistently and publicly said over the last two weeks that the commentary and debate relating to internal party matters, especially the Liberal Leadership, must come to an end”.