Supporters of Prime Minister Tony Abbott believe today's leadership spill motion will fail despite his approval rating falling to a record low.

As the Liberals get set to vote on Tony Abbott's leadership, the coalition has recorded its worst Newspoll result since 2009 with the prime minister trailing behind Communications Minister Malcolm Turnbull as preferred PM 25 percent to 64 percent.

The Newspoll, which was conducted over the weekend for The Australian newspaper, also shows deputy leader Julie Bishop leads as preferred leader 59 percent to 27 percent.

Liberal MPs and senators will gather at Parliament House today at 9am (AEDT) to vote on a leadership spill motion brought by West Australian MPs Luke Simpkins and Don Randall.

The prime minister's performance rating has fallen nine points to 24 percent - significantly below his previous low in June of 30 percent.

NOT LOOKING SO HOT: Prime Minister Tony Abbott. (AAP)

Compared with the two likely contenders for the LNP leadership - Mr Turnbull and Ms Bishop - Mr Abbott is easily the least popular of the trio.

Mr Simpkins says voters have lost faith in Mr Abbott and members should be given a say on the leadership and the direction of the government.

However, Mr Abbott's supporters believe those pushing for the spill number in the 30s in the 102-member party room - well short of the majority needed to succeed.

Spill proponents say their numbers are in the 40s.

LOOKING GOOD: Malcolm Turnbull.

Neither Malcolm Turnbull nor Julie Bishop - the two prospective contenders - have publicly said they will stand against Mr Abbott should the spill motion succeed.

But party sources say the pair are sounding out colleagues.

There is anger in the party room that Mr Abbott brought forward the vote which was originally scheduled for Tuesday.

Last night Mr Abbott revealed the spill motion was a “chastening experience” - especially coming only 17 months into his term.

STILL BETTER: Julie Bishop is still out in front of Mr Abbott according to the latest poll. (AAP)

“I am determined my government, if it continues after tomorrow, will learn from this experience, will be different and better this year than we were in every respect last year,” he told the ABC.

Meanwhile, the coalition's primary vote is down three points to an eight-month low of 35 percent.

Labor is up two points to 41 percent, and the Greens are unchanged at 12 percent.

In two-party terms, the government's vote is down to 43 percent, with Labor on 57 percent.