'All the right causes': Miranda Devine and Coalition senators back extreme Queensland candidate

A Toowoomba doctor who advocates gay conversion therapy has been endorsed for Liberal National party preselection by a host of conservative figures, including sitting senators Matt Canavan and Eric Abetz, the former deputy prime minister John Anderson and the News Corp columnist Miranda Devine.

David van Gend believes homosexuality is “a potentially treatable psychological condition”, opposes legal abortion and disputes scientific evidence of global heating.

Guardian Australia revealed on Tuesday that Van Gend had the backing of the LNP’s influential “Christian soldiers” faction and probably had the numbers to win preselection for the safe federal seat of Groom.

LNP members will choose their candidate in Toowoomba – a stronghold for the party’s religious right – on Sunday. The byelection in the federal seat of Groom, set for 28 November, was caused by the sudden resignation last month of the sitting member, John McVeigh.

In an endorsement document circulated to party members, Canavan said: “We need people like David in the trenches in Canberra to promote our wealth-producing industries and defend family values with integrity and determination.”

Related: Christian soldiers and climate deniers: inside the fight for control of the Queensland LNP

Anderson, the former Nationals leader, recorded a video message for preselectors.

“He’s the sort of person we say we want representing us, and Australia really does need people of his intellect, and I believe of his persuasions, to put the case powerfully as we struggle as a country on so many fronts,” Anderson said.

Endorsements were also written by the Institute of Public Affairs executive director, John Roskam, former Nationals senator Ron Boswell, contrarian academic Peter Ridd, and commentator Rowan Dean.

Devine wrote that “Groom is lucky to have a man of David’s calibre willing to serve in parliament”.

“David is a happy warrior for all the right causes,” she said.

In his own letter to preselectors, Van Gend wrote about pandemic recovery but that he also wanted to help the nation recover from “another kind of sickness: the cultural sickness that has been brought about by the long march of the left through our institutions”.

“There is no point in the LNP controlling the finances of our nation if Labor and the Greens control the minds of our kids.”

The preselection will take place six days before the Queensland election, and party moderates and some officials are increasingly panicked about its implications for the state poll.

The party’s state leader, Deb Frecklington, has sought to downplay conscience issues amid a push from the religious right to wind back abortion laws and oppose voluntary assisted dying.

LNP sources are concerned that if the party endorses Van Gend, Frecklington would spend the final week of the campaign fending off suggestions the party was in thrall to its most extreme elements.

Increasingly, moderates are growing frustrated with the party’s pivot towards conservative social positions. A former LNP policy committee chair and state councillor, Stephen Thornton, told Guardian Australia there were few real moderates still in the Queensland party.

Related: Queensland election: LNP tries to keep anti-abortion push out of sight

“In my view, this election is the time when moderates should consider putting their vote with someone other than the Queensland LNP, possibly Labor or the Greens,” Thornton said.

“My issue is not with Frecklington, but my view is that the party behind her, if they got into government, won’t let her run her own race, they would be pushing to look at abortion laws.”

The former Newman government minister Jann Stuckey quit the party earlier this year after retiring from parliament. She has previously told Guardian Australia the LNP has been “slowly but steadily taken over by the religious right”.

LNP sources say they believe Van Gend has the numbers to win the Groom preselection.

Guardian Australia has also seen a video endorsement by Ian Macfarlane, the former Groom MP and now head of the Queensland Resources Council, for a rival candidate, Toowoomba councillor Rebecca Vonhoff.

“She is the person that will represent the whole community, every aspect of it,” he says.

Van Gend has not returned Guardian Australia’s calls.