Senators Ted Cruz and Mitch McConnell criticized Mr. Carlson, as well as Kevin Roberts, the president of the Heritage Foundation, who defended Mr. Carlson as a “close friend.”

Although Fuentes has many dedicated fans, who call themselves “Groypers,” mainstream conservatives have long ignored him. Even as the Republican Party has come to embrace more extreme ideologies, he has been seen as too radioactive: Fuentes has praised Hitler on multiple occasions,

The Berwyn white nationalist, who one researcher says is positioning himself as the "alt-Charlie Kirk," has made a series of podcast appearances recently, including on Tucker Carlson's show this week.