Campbell Newman (Imag: AAP/Lukas Coch)

With the slow pace of the vaccine rollout already putting its reelection prospects in doubt, the Morrison government has emerged from the weekend with new headaches arising from a growing conservative rebellion over COVID-19 management.

The most visible manifestation was Saturday’s anti-lockdown protests, which were attended by a government MP in George Christensen and a prominent Liberal Party activist in John Ruddick, who has defected to the Liberal Democrats and will run as the party’s candidate in Tony Abbott’s old seat of Warringah.

While none of this would have come as too much of a shock to anyone familiar with either individual’s track record, it was followed overnight by the genuinely startling news that former Queensland premier Campbell Newman had quit the Liberal National Party with a view to running against it in the Senate.

The Australian has reported that Newman is also likely to throw his lot in with the Liberal Democrats, although he is understood to have also had talks with One Nation and Clive Palmer, and could end up running as an independent.

While Newman has never been lacking in self-confidence, it can hardly be denied that he has himself a difficult task. Since there seems little prospect that the parties of the left will lose yet more ground in Queensland at the next election, a Senate seat would have to come at the expense of either Pauline Hanson or Amanda Stoker, who will hold the third position on the LNP ticket.

With group voting tickets abolished in 2016, the days when Newman might have hoped to get up through adroit preference dealings with micro-party networks are long gone.

Now that voters make up their own minds about which party boxes to number, preferences are strongly favouring known quantities. That has meant meagre pickings for the likes of the Liberal Democrats, with micro-party preferences in Queensland flowing heavily to One Nation and, to a somewhat lesser extent, the LNP, Labor and the Greens.

No doubt Newman’s name recognition would improve things, but it seems likely that a successful Senate bid would have to come despite small party preferences rather than because of them.

Newman will thus need to outpoll either One Nation or what remains of the LNP vote after its first two candidates are elected, and then be pushed over the line on their preferences. That hurdle would exceed 10% if the 2019 result was repeated, although polls and state election results, together with the fact of competition from Newman, suggest neither the LNP nor One Nation will do as well this time.

While that should helpfully lower the bar, Labor could potentially gain an extra seat if it forms part of a substantial drop in the overall right-of-centre vote, in which case Newman’s path to victory would become very narrow indeed.

To stand a realistic chance, Newman will thus have to persuade the better part of one in 10 Queenslanders to give him their first preference, which he is evidently hopeful of doing through a combination of his personal drawing power and the niche of anti-lockdown sentiment that found expression on Saturday.

While the limitations of the former were demonstrated by his government’s unceremonious defeat after one term in 2015, Newman’s uncompromising style as premier seems to have won him lasting admiration among LNP voters. A recent Ipsos poll found about 60% (out of an admittedly small sample of 173) maintained a favourable view of him.

What’s less clear is why voters in Queensland would turn on the Morrison government specifically over lockdowns imposed by state Labor, which have in any case been greatly less demanding than those endured by Sydney and Melbourne.

And while Newman would undeniably bring extensive political experience to the Senate, it’s at best arguable that his election would be a net benefit to conservative politics if it came at the expense of a rising Coalition star in Stoker.

Worse still, his presence in an already crowded field could simply serve to split the vote and dilute the flow of preferences between the various right-of-centre candidates, potentially adding an extra Labor or Greens member to a precariously balanced Senate.