If the Barnett government is defeated, not only will Malcolm Turnbull have to contend with one more state Labor government but the Coalition backbench and the wider conservative constituency will become even more agitated in an already volatile climate. Turnbull has had virtually no role in the campaign but that wouldn’t protect him from the fallout of a Liberal defeat.

Equally important, the state election is being watched as a major test of Pauline Hanson’s pulling power.

The preference deal between the Liberals and Hanson, at the expense of the furious Nationals, marks a new phase in relations between mainstream conservatism and the maverick right-wing outlier. If Hanson polls well, that will reinforce the pressure for preference deals, first at the coming Queensland election – where a deal already seems extremely likely – and then at the federal election.

But much will depend on how the Hanson vote is read. If she polls say, 10%, this can be interpreted as strong or as a disappointment when measured against earlier hints that she might do much better.

The disruptive force of Hanson, even amid an imploding party, has been on full display in recent weeks.

The WA preference deal – under which the Liberals preference One Nation over the Nationals for the upper house and One Nation puts Labor behind the Liberals for the lower house – has angered both Liberal and One Nation supporters.

Potential One Nation voters are looking for a party that disses the system – they don’t want to be told to support, albeit indirectly, the unpopular Barnett government. Hanson will pay a price if they think she has gone from the “outsider” to an “insider”.

For his part, Colin Barnett has had to protest endlessly that he’s not really in bed with Hanson and her mates. “Can I stress there’s no agreement with One Nation. I don’t endorse their policies. I don’t endorse their candidates and there is no agreement about any role in government about legislation or policy,” is his mantra.

The backlash from some Liberal supporters highlights the danger of Liberals anywhere in the country cosying up through preference arrangements to One Nation, whose attitudes are anathema to many on the conservative side of politics.

Hanson has spent the last week of the campaign in the west, particularly in regional areas, where the party hopes the preference deal will give it a balance-of-power role in the upper house.

The paradox of her campaign is that she is greeted as a celebrity on the streets, while members of her party have been turning on her bitterly.

Eighty-seven-year-old Ron McLean and his 79-year old wife, Marye Daniels, who have hired a high-profile lawyer, say Hanson dumped them last month from their party positions. McLean, who had been WA party president and a candidate for the upper house, claimed Hanson had said he was too old and would be 91 at the end of the parliamentary term. One Nation counter-claimed that it was about disloyalty and McLean’s health.

Polling analyst William Bowe says One Nation’s campaign has been “a bit of a shambles”. But he raises the question: “With respect to how well they’re going to go … how much does that matter?”

Just as the WA Liberals have been trying to defend their dubious deal with One Nation, Hanson has made their task more difficult by her inflammatory statements this week.

Hours before arriving in WA she told the ABC on Sunday that parents should do their own research before having their kids vaccinated, and she waxed lyrical about Vladimir Putin. The following day she was back on her Muslim jihad, saying they had changed Australian suburbs and questioning how one distinguished a good Muslim from a bad Muslim.

Malcolm Turnbull rounded on her on all three fronts. But former Queensland Nationals senator Ron Boswell, who trenchantly fought Hanson two decades ago, suggested the Liberals have given comfort to her. He pointed to federal cabinet minister Arthur Sinodinos’s observation some weeks ago that One Nation had become “a lot more sophisticated”.

Boswell told Guardian Australia he was worried that the conservatives were not taking Hanson on, but just thinking about the short term. Comments like those of Sinodinos were legitimising her – “making it safe for people to vote for her”.

The Hanson deal is a measure of Barnett’s desperation. Although Labor has to win 10 seats to govern, requiring a uniform swing of 10%, polls have put Opposition Leader Mark McGowan on track for victory.

Barnett attributes his troubles to the longevity of his government, which was elected in 2008, but the state’s economic woes and the budget’s debt and deficit crisis have driven away voters. The end of the mining boom has seen a remarkable turnaround in a state that only a few years ago was riding high on the hog. Hit by job losses and collapsing house prices, many people are in shock.

Barnett’s proposal to privatise 51% of Western Power, the polls and wires network, to help tackle the budget crisis is a hard sell to a sceptical public.

One complication for Barnett is that he has been open about the fact that he would not serve a full term if re-elected. It might be commendable frankness but, for voters, it adds more uncertainty.

If he wins, McGowan’s victory will be largely because people just want to see the end of Barnett, who trails his opponent as preferred premier. It’s not that they hate him, but rather many voters simply think his time is over.

McGowan, a one-time naval lawyer and a former minister, is an experienced and competent technocrat. He mightn’t be very charismatic but still, given the campaign polls, the attempt by former federal minister Stephen Smith (not even a state MP) to replace him in the leadership last year seems even more extraordinary in retrospect than it did at the time.

If Barnett hung on, it would be in minority government, dependent on his alliance partner the Nationals. The dynamics of the now deeply aggrieved Nationals operating in the new government with the Liberals would be fascinating. They would be even more willing than in the past to play tough to get what they wanted.

If McGowan wins, one of his early challenges would be to deal with Canberra and other premiers. He declares he would fight for a better deal on that perennial burr under the saddle for WA – its slice of the GST. This would require persuading fellow first ministers – and when it comes to money, state leaders put aside any fraternal party loyalty in pursuit of their own interest.

Turnbull has threatened that if McGowan as premier tried to dump Barnett’s road infrastructure plan in favour of Labor’s rail scheme, he wouldn’t get promised Commonwealth funding.

A defiant McGowan says Turnbull is bluffing. How does he know?

“If they don’t work with the West Australian government to give us our fair share, the electorates of Pearce, Hasluck, Swan, Canning, Stirling, will be lost to the Liberal Party. Self-interest always wins out and so they will do the right thing – because Christian Porter will be the first one to fall.”

Michelle Grattan is a Professorial Fellow at the University of Canberra.

This article was originally published on The Conversation. Read the original article.