Dan Cox, an extremist pro-Trump Republican, won his party’s nomination for governor in Maryland last week thanks to “collusion between Trump and the national Democrats”, the current Republican governor said.

“I don’t think there’s any chance that [Cox] can win,” Larry Hogan added, speaking to CNN’s State of the Union.

Hogan previously called Cox “a QAnon whack job”.

“Collusion” is a loaded word in US politics, in the long aftermath of the Russia investigation, in which the special counsel Robert Mueller scrutinised election interference by Moscow and links between Trump aides and Russia.

The battle to succeed Hogan as governor of Maryland might seem small beer in comparison. But the race attracted national attention.

Cox, endorsed by Donald Trump, surged past Kelly Schulz, a member of Hogan’s cabinet, to win the Republican nomination.

In the Democratic race, Wes Moore, a bestselling author, beat candidates including Tom Perez, a former Democratic national committee chair and US labor secretary.

In a midterm election year, Democrats have sought to boost pro-Trump Republicans in competitive states, placing the risky bet that as the January 6 committee remains in the headlines, extremists who support the former president’s lie about electoral fraud in his 2020 defeat will prove unpalatable to voters.

Hogan said: “There’s no question this was a big win for the Democratic Governors Association that I think spent over $3m trying to promote this guy [Cox]. And it was basically collusion between Trump and the national Democrats, who propped this guy up and got him elected.

“But he really is not a serious candidate.”

The New York Times reported the sum spent by the DGA on pro-Cox TV ads at “more than $1.16m”.

Hogan’s host, Jake Tapper, pointed out that 142,000 Republicans voted for Cox, a state legislator, “So it’s really Republican voters that did this.”

Hogan said: “Yes, well, some of them. I mean, we only have a little over 20% of the people in Maryland are Republican, and only 20% of them showed up at the polls. So it’s about 2% of the people of our state that voted for the guy. And in the general election, I think it’s going to be a different situation.”

Hogan has sought to establish himself as a figurehead for anti-Trump Republicans. Asked if he would vote for Moore, he said he would “have to make a decision about that between now and November. But I’m certainly not going to support this guy [Cox]. I said I wouldn’t. He’s not qualified to be governor.”

Cox tried to impeach Hogan over his handling of the Maryland Covid response. He has used QAnon-adjacent language and attended a QAnon-linked convention.

QAnon is an antisemitic conspiracy theory which among other beliefs holds that the US is run by a cabal of child-molesting cannibals which Trump will defeat.

Hogan has said he is considering a run for the Republican presidential nomination. He was not drawn further on the matter on Sunday.

He did tell ABC’s This Week he thought a Trump 2024 announcement before November, which seems likely, would cost Republicans in the midterms.

“We had discussions about that at the Republican Governors Association last week,” he said, “and I think most people are very concerned about the damage it does to the party if he announces now.

“And, you know, it may help in very red states or very red districts. But in competitive places and purple battlefields, it’s going to cost us seats if he were to do that.”

Hogan said he thought Trump’s “ego probably can’t take another loss – after all he lost to Joe Biden, which is hard to do – but he likes to be the center of attention”.

On CNN, Tapper cited Liz Cheney, another anti-Trump Republican and possible presidential hopeful who seems set to lose her US House seat in Wyoming, and asked if Hogan felt Trump was winning the battle for the soul of his party.

“There’s no question that we lost a battle and we’re losing a few battles,” Hogan said. “But the fight is long. It’s long from being over.

“I mean, we have another couple of years before the next [presidential] election. In November of ’20, I gave a speech at the Reagan Institute saying, ‘There’s going to be a long battle for the heart and soul of the Republican party and this is just the beginning.’

“I think, in November, we’re going to have a different story, when a lot of these fringe candidates lose. And then we’re going to have to start thinking about, between November’s election and the election two years later, what kind of a party are we going to be? And can we get back to a more Reaganesque big tent party that appeals to more people?

“Or are we going to double down on failure?”