Home Affairs Minister Peter Dutton has thrown his support behind Jim Molan to return to the Senate for the Liberal Party in NSW.
Mr Molan is firm favourite as Liberal preselectors prepare to decide on Sunday who will replace Arthur Sinodinos, but some in the left of the party are marshalling troops against the retired major-general.
"He did an exceptional job as a senator when he was in the Senate and hopefully he can continue that work," Mr Dutton told 2GB radio on Thursday.
The prime minister has also endorsed Mr Molan.
"Ultimately, though, these matters are up to preselectors and they don't take kindly to gentle persuasion from members of the party otherwise," Mr Dutton said.
"It's an individual decision but when you look at the merit of his case, he's got a great case to put. He's served his country in uniform and he's gone on very proudly to represent us in the Senate.
"I think he stands up for the vast majority of Australians and I hope he can come back into the parliament."