Conservative Liberal senator Jim Molan has committed to running for the party at the next election, dousing speculation he could switch to a minor party.
The former major general has been preselected at No. 3 on the Liberals' NSW Senate ticket, a position which will make it difficult for him to keep his seat.
Rather than jump ship to a minor right-wing party like One Nation or the Liberal Democrats, Senator Molan is clinging to the slim chance of winning the election through a strong below-the-line vote.
"I intend to run as a Liberal in the next election so that those that support me can vote for a Liberal from a conservative base," Senator Molan said in a statement.
Labor senators used question time to ask why Prime Minister Scott Morrison had intervened to save Liberal MP Craig Kelly from losing preselection, but not a man who had served his country.
Government Senate leader Mathias Cormann said Labor should join the Liberals' campaign to get four NSW senators elected.
"Senator Molan is an endorsed Liberal Party candidate at the next election," Senator Cormann said.
"The prime minister of course holds Senator Molan in very high regard."
Shortly after question time, Senator Molan confirmed Mr Morrison was not going to step in to elevate him to a more winnable position on the NSW ticket.
"This afternoon, I have been told that I can expect no special intervention from the prime minister regarding the order on the Senate ballot," Senator Molan said.
"I will continue to work hard for veterans, national security and the people of Australia."
Earlier in the week, Senator Molan said "all options are still open to me" when asked about his future.