Exceptions of course came from the fake church leaders who had infiltrated God's churches then just like now. But make no mistake: the main push for scientific racism came from the secularists.
https://www.americanthinker.com/articles/2025/07/secular_mythology_the_scopes_monkey_trial.html
That seems like a simplistic and misleading dichotomy. Among those with interest in the subject, there were many Christians who were not fundamentalists, and many secularists who were not racist white supremacists.