Mr. Trump signaled in a social media post on Monday that he could usher in changes at the national committee in the next few weeks.
“Ronna is now Head of the RNC, and I’ll be making a decision the day after the South Carolina Primary as to my recommendations for RNC Growth,” he wrote, calling Ms. McDaniel a “friend.”
South Carolina will hold its Republican primary on Feb. 24.
While he holds no formal power over the group, it is commonplace for the party’s standard-bearer — which Mr. Trump, as the Republican front-runner, very much is — to wield significant power over the committee.
His remarks on Monday expanded on his less-than-glowing assessment of Ms. McDaniel’s performance during an interview on Sunday on Fox News. When he was asked how she had been doing as the committee’s leader, Mr. Trump praised Ms. McDaniel for her previous role in helping him win Michigan during the 2016 election, when she was the state party chairwoman.
“I think she did OK initially in the R.N.C.,” he said. “I would say right now there will probably be some changes made.”
Shane Goldmacher contributed reporting.