White evangelicals have dropped to 13.6% of the population (and Christian nationalists would be a tiny subset - keep in mind, tho, that there are many non-white evangelical Christians) 

....The group that has declined the most is at the core of the MAGA movement, the group most devoted to Christian nationalism. “White evangelical Protestants have experienced the steepest decline. As recently as 2006, white evangelical Protestants comprised nearly one-quarter of Americans (23%). By the time of Trump’s rise to power, their numbers had dipped to 16.8%,” Jones explains. “Today, white evangelical Protestants comprise only 13.6% of Americans.”

And that decline may yet accelerate, because they skew older than the population as a whole. Put differently, there are far more baby boomers in this group than Generation Z members. White evangelicals are “losing” people with each successive generation. (“White Christian subgroups have each lost approximately half their market share just across the generations who are alive today,” according to Jones.) If your business had lost half its market share, you would be panicking, too.....

from Opinion - Why white Christian nationalists are in such a panic