As controversy continues to cloud some of President-elect Donald Trump’s Cabinet picks, his team has an ominous warning for Republicans who don’t fall in line behind his nominees.

ABC News Chief Washington Correspondent Jonathan Karl reports that one senior Trump adviser said the message to lawmakers is, “If you are on the wrong side of the vote, you’re buying yourself a primary.”

“That is all,” the adviser told Karl. “And there’s a guy named Elon Musk who is going to finance it.”

“The president gets to decide his Cabinet. No one else,” the adviser added.

The threat comes as Matt Gaetz and Pete Hegseth (tapped for attorney general and defense secretary, respectively) make the rounds on Capitol Hill this week to shore up support. They’re being escorted by Vice President-elect JD Vance, the junior senator from Ohio.

Gaetz faces allegations of sexual misconduct and illicit drug use, which he’s long denied, that was the subject of a federal investigation and a House Ethics Committee probe. Hegseth has been accused of sexual assaulting a woman in 2017, an encounter Hegseth told police was consensual.

Trump is standing firm with the selections, which had also raised eyebrows for their relative lack of experience to lead the Department of Justice and the Department of Defense.

But for Gaetz especially, confirmation is no guarantee. Republicans will have a slim, three-seat majority in the Senate.

Already, two GOP senators — Susan Collins and Lisa Murkowski — have signaled opposition to Gaetz, though they haven’t officially said how they would vote. Sen. Kevin Cramer told ABC News Senior Congressional Correspondent Rachel Scott last week that if the vote were to happen now, Gaetz wouldn’t pass muster.

Trump previously made a demand for Republican leadership to back so-called “recess appointments” to skirt the traditional confirmation process. That route would require lawmakers to adjourn and for senators to give up the “advice and consent” role they play in nominations, as laid out in the Constitution.

But his demand is being met with some resistance from some Senate Republicans

Sen. Thom Tillis, a senior Republican and member of the Senate Judiciary Committee, said recess appointments for Cabinet posts should be “absolutely off the table.”

“And quite honestly, any serious candidate for Cabinet-level position, I would really have to wonder if they would want it or be willing to accept it under a recess,” Tillis said. “These positions are too important. They carry too much weight internationally to take a short cut.”

Several senators have said they want the full “process” and vetting of candidates to play out.

“The Constitution gives us a role in personnel called advice and consent. My view is that’s exactly what will unfold here when these nominees are actually sent forward, and we’ll treat them like we’ve treated all others with the proper vetting,” said longtime Senate Republican Leader Mitch McConnell, who recently stepped down from the role.

Sen. Josh Hawley, who met with Gaetz on Wednesday, said on Wednesday his intention to vote for all nominees.

“I think for my colleagues who are — who have concerns about the attorney general nominee, my message would be, well, let’s have a hearing on this,” Hawley said. “You can ask whatever — if you’re a member of the committee, you can ask whatever question you want, give Gaetz the opportunity to answer questions, lay out his vision, answer concerns.”