More than that, he made it abundantly clear that he's "Team Trump" through and through. This bold move must have sent shivers down the rickety old spines of the GOP establishment.

NBC News:

House Speaker Mike Johnson took sides in the presidential primary on Tuesday, endorsing former President Donald Trump.

Johnson's endorsement breaks with his predecessor, former Speaker Kevin McCarthy, who had declined to back a candidate in the GOP primary. Party leaders from both sides in Congress have often stayed neutral until a presumptive nominee emerged from the primaries.

"I'm all in for President Trump," Johnson told CNBC's "Squawk Box" on Tuesday. "I expect he'll be our nominee. He's going to win it and we have to make [President Joe] Biden a one-term president."

Trump had praised the Louisiana Republican during the speaker fight, nicknaming the four-term congressman "MAGA Mike Johnson" in one post on his Truth Social platform.

Johnson was a vocal proponent of Trump's false claims that the 2020 election was stolen, leading an amicus brief supporting a Texas lawsuit aimed at tossing out results from four critical states.

Here's part of what Mike said during his interview: "I have endorsed him wholeheartedly," Johnson said. "Look, I was one of the closest allies President Trump had in Congress. He had a phenomenal first term. Those first two years, as you all know, we brought about the greatest economic numbers in the world and not just the country because his policies worked, and I am all-in for Trump. I expect he will be our nominee, and he will win it, and we have to make Biden a one-term president. We have to do that."