Half a dozen National MPs are jockeying to become Barnaby Joyce's new deputy but the party room could hold off on a vote until it becomes clear whether Fiona Nash - who lost the job to dual citizenship - has a pathway back into the Senate.
Outspoken Queensland cabinet minister Matt Canavan, who survived his own dual citizenship scare, is considered the frontrunner, but is facing a likely challenge from NSW MP Michael McCormack and Victorian Bridget McKenzie.
Junior ministers David Gillespie and Keith Pitt, as well as backbencher Kevin Hogan, may also have a tilt at the job, which comes with a guaranteed spot in cabinet.
Absent from the list is fellow cabinet minister Darren Chester, who lacks the necessary party room support and is understood to be backing Senator McKenzie.
The party room will meet on Thursday morning, with Mr Joyce back in charge following his thumping win at the New England byelection on Saturday.
But while the MPs were expected to elect their new deputy during the meeting, some are now pushing to delay a vote until Ms Nash's future becomes clearer.
Ms Nash was ruled ineligible by the High Court but her replacement - Liberal Hollie Hughes - was also ruled out under section 44 of the constitution. The court will publish the reasons for its Hughes verdict on Wednesday but it is unclear whether it will make orders about a replacement.
If the court orders a countback, the replacement will be hard-right Liberal and Tony Abbott ally, Jim Molan. But if it orders a casual vacancy the Coalition would get a choice. In that scenario, the Nationals would fight hard for Ms Nash's return, setting up a clash between the Coalition partners.
"There potentially is a pathway back," Ms Nash told Sky News on Tuesday.
"If there is a casual vacancy I'd be very keen to come back. And I know the National Party would be very keen to keep the National Party seat in the Parliament."
Asked if she wanted the party room to hold off on voting, Ms Nash said: "I certainly believe I have done a good job and I hope people think I've done a good job as deputy leader. I would hope that colleagues would think about that while they're considering whether or not they need to change deputy leader this week."
The jockeying within the Nationals came as Labor came under further pressure to refer at least three of its MPs to the High Court over citizenship doubts. Senator Katy Gallagher and lower house MPs Justine Keay and Susan Lamb all remained dual citizens when they nominated as candidates last year.
Shadow attorney-general Mark Dreyfus said Labor had not ruled out referring Senator Gallagher to the court, but maintains it would be a waste of time and taxpayers' money. Labor maintains their MPs are protected from disqualification because they took "reasonable steps".
If Labor refuses to refer the MPs, the government could do it itself with the help of the Greens.