The Liberal frontbench will undergo a shake-up with Treasurer Joe Hockey a very likely target, following Malcolm Turnbull’s successful leadership challenge, 9NEWS Political Editor Laurie Oakes said.

“Joe Hockey will have to go, there’s no doubt about that,” Oakes said.

“Joe Hockey’s regarded as almost as much as a problem for the government as Tony Abbott.”

“Scott Morrison, I’m certain, will become Treasurer and Julie Bishop, as we heard, remains Deputy Leader.”

Mr Oakes said Kevin Andrews would not have expected to win his contest of deputy leader in tonight’s ballot.

“Kevin Andrews’ ran, I think, just as a gesture; he would’ve known he was going to get wiped out – pretty silly gesture, really, but it does show that there is bitterness there,” he said.

“Joe Hockey, Kevin Andrews, Mathias Cormann, and other Ministers who remain loyal to Tony Abbott earlier tonight were pretty scathing about Malcolm Turnbull.”

Mr Turnbull almost resigned from politics after Tony Abbott won leadership from him in December 2009, Mr Oakes pointed out.

“He announced then, after he lost that he was going to leave politics, and he’d made all the arrangements, but then he was persuaded that he should change his mind… serve on the frontbench under Tony Abbot, he’s done that and now he’s Prime Minister” Mr Oakes said.

Earlier tonight, Oakes said that if Mr Turnbull was successful, he would become Australia's fifth Prime Minister in as many years.

Oakes said Mr Turnbull has given private undertakings that if he becomes Prime Minister he will not push his views on climate change, he'll stick to the current policy.

"The right wing of the Liberal Party basically doesn't like Mr Turnbull, they were the ones who got rid of him when he was Opposition Leader and installed Tony Abbott in his place," Oakes said.

"Some of those right-wingers as I understand it have no said that they are prepared to serve with Mr Turnbull, well if that's the case then he should have the numbers."

Referring to Mr Turnbull's very direct criticisms of Mr Abbott during his speech , Oakes said that one of the mistakes Labor made when Kevin Rudd was dumped as Prime Minister was that they didn't clearly explain the reasons for doing so.