The stark and public split has come just days before polling and after Liberal leader Scott Morrison spent close to five campaign weeks insisting his party was united.
Former Nationals leader Barnaby Joyce underlined the discontent by telling the Liberal rebels, “Your result will be ashes in your mouth.”
And he urged voters to defy instructions by putting Nationals candidate Perin Davey in the top winnable spot on ballot papers.
At issue is an attempt to have sitting Liberal senator Jim Molan elected on Saturday, even though he has been preselected for the unwinnable number four position on the Coalition ticket.
Voters are being urged to ignore the official party how-to-vote directions and put Senator Molan at number one on their ballot papers.
That effectively would push the Nationals candidate, Ms Davey, from the number three slot to the unwinnable number four.
The relegation of Ms Davey would be a breach of the Coalition agreement, Barnaby Joyce told ABC radio today.
And he questioned whether the agreement would survive what he called a “fractured” vote.
“Well we have an order, we have a process, and you’ve got to abide by the agreement,” Mr Joyce said.
“If you don’t abide by a key tenet of the agreement then it calls into question what is the strength of that agreement.”
Mr Joyce said the Nationals, and predecessor the Country Party, had held a NSW Senate seat in every Parliament since Federation.
He said it was important for Parliament to have “a person from a genuine western regional town to represent us in the national Senate” and advocated rejigging the Coalition ticket.
“If you want more women in politics — and we hear that all the time — well then vote Perin Davey at number three, but you have to put a number one beside her name and do the numbers,” he said.
The Nationals are particularly peeved because Senator Molan was not elected to Parliament. He got the job after Nationals senator Fiona Nash was forced to stand down over dual citizenship issues.
He was put at number four on the ticket to reflect that accidental elevation.
However, he has emerged as a prominent conservative figure in the Liberal Party and a participant in internal activism against policies of former prime minister Malcolm Turnbull.
The contest for the six Senate slots in Australia’s biggest state is always fierce with Labor likely to win at least two positions, the Coalition two, and the final two possibly shared by the Greens or the two majors.
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“To get three in (Parliament) these days is incredibly difficult and it requires total concentration and discipline to get that across the line,” Mr Joyce said.
And he warned rejection of the official ticket by Molan supporters could allow “a Fraser Anning candidate to take your space, or a Green candidate to take your space, and if that’s the way you want your Senate to go, well, good luck”.