From the article:
Michigan: 54%
North Carolina: 54%
Ohio: 61%
Nevada: 56%
“This means the president’s rallies are not only energizing his base, but also introducing new voters to his endorsed candidates in the critical days before the midterm elections,” the official said. “This is the kind of energy that fuels massive victories.”
There are tons of MAGA patriots in Fresno, Bakersfield, or Modesto. But if Trump held a rally in any of those cities, it would be 95% new attendees, even if 0% were recent converts. That's for reasons unrelated to the movement's growth.
Even so, it's growing. No matter how you slice it. NCSWIC.