Palmer United's Zhenya 'Dio' Wang claims the Coalition has "stopped governing" and Prime Minister Malcolm Turnbull should immediately call a double dissolution election to allow Australians to decide the way forward for the federal government.
And in a bold move for a politician whose term would not end until 2019 if a double dissolution is avoided, Senator Wang said he "hopes Labor get into government" after a snap poll.
"If [the Coalition] are not negotiating, if they are not governing, then it's in everyone's interests, but mainly the public's interest, to have an election," Senator Wang told Fairfax Media in an interview on Tuesday.
"Labor are easier to deal with and we would hope they get into government. I am disappointed at the inaction of the government."
Senator Wang, who is the Palmer United Party's only remaining senator, said he was not concerned at the prospect of returning to the private sector if he lost his seat in an early election.
Reeling from the lightning introduction of senate voting changes likely to wipe out the majority of the crossbench by preventing "preference harvesting", crossbenchers met together on Tuesday.
He said the mood was: "Don't threaten us, get stuffed."
As recently as Friday, Senator Wang had been negotiating possible amendments to the government's bill to reintroduce the Australian Building and Construction Commission - a possible double dissolution trigger if it is rejected again by the senate.
But he now believes that bill is "dead" and that the government is intent on a swift double dissolution anyway.
"They are tanking in the polls and [Senate voting reform] is a huge distraction," he said.
Fairfax Media understands Glenn Lazarus, Jacqui Lambie, Ricky Muir and John Madigan would still vote down the ABCC bill in its current form and David Leyonhjelm and Bob Day, who has previously been supportive, would consider abstaining in reaction to the voting reforms.
The government needs the votes of six of the eight crossbenchers because Labor and the Greens are opposed to the resurrection of the ABCC.
A Senate committee looking at the ABCC bill is due to report back on March 15 – two days before Parliament rises for the pre-budget break.
On Tuesday, Senator Day described the government's proposed voting reforms as a "bombshell", claiming they could be unconstitutional because they disenfranchise voters by exhausting votes that would otherwise have remained live in the current preference system.
"[The government] has effectively signed our death warrant," Senator Day said.
Senator Day said he had taken initial legal advice on the reforms and had a senior barrister willing to represent him to challenge them in the High Court if they were passed.
He said they breached section 7 of the constitution, which states that senators of each state shall be "directly chosen by the people of the State, voting, until the Parliament otherwise provides".
The reforms, he said would "disenfranchise over three million voters at the next election because basically (those who) voted for minor parties at the last election, their votes will die. Most will just vote one above the line and their vote will die."
Constitutional law experts said such a challenge was highly unlikely to succeed.
Australian Catholic University vice-chancellor Greg Craven said: "The High Court has always made it clear that there are a range of electoral systems that can (satisfy direct election)."
"The High Court would throw it out like yesterday's potato peel," he said.
University of NSW law Professor George Williams agreed, saying the reforms were no more vulnerable to being unconstitutional than the current system: "Choosing between competing electoral systems is a matter for Parliament and you'd need something more problematic to raise a real constitutional concern."
Voting reforms would have to shut out a significant section of the population, for example all women, to legally disenfranchise voters, he said.
With Jane Lee