The Australian Motoring Enthusiast Party senator fired the "preference whisperer" overnight.
Senator Muir has released a statement confirming the move, stating that "the reasons for his dismissal remain private between myself and Mr Druery".
SBS has contacted Mr Druery for comment.
Mr Druery was widely credited as the brains behind the deals that helped Senator Muir and the Palmer United Party win Senate seats at the September election.
The development follows a move by the Australian Motoring Enthusiast Party Victoria to kick the novice senator out of the party.
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The group called an annual meeting on Wednesday evening, where a motion of no confidence in Senator Muir was moved.
In a statement posted on the group’s Facebook page, members voted that Senator Muir should be considered an independent.
“His endorsement has been withdrawn by AMEP Vic, he has been expelled from the AMEP Vic branch, his membership revoked and he is no longer recognised as a representative of Vic motoring enthusiasts,” it read.
“There are now insufficient financial member numbers, at the Vic branch level, to satisfy the constitution and the AEC official state representation criteria and as such, proceedings have commenced to ‘wind-up’ / cease official operations of the AMEP Vic branch.”
Senator Muir has also come under fire on his new Facebook page, where some commenters have called on him to represent the “beliefs” of the party.
Senator Muir has since stressed his ongoing membership online.
