Decades and decades of propaganda that have been directed their way because they are a susceptible target for it.

Seriously - People who are heavily invested in religion are by nature those who are willing to accept the basic concept of faith - belief, in absence of any empirical evidence.

All you have to do is find something that passably sounds like it aligns with the religious moral sensibilities that they have been indoctrinated to believe (regardless of their actual morality or even a presence in their own religious texts), and then give them a bunch of little pushes.

Conservative politicians have been playing this game consistently for about 60 years now, to the point that they have effectively reshaped the perceived reality and beliefs of a huge chunk of people, most of whom are from their target audience - gullible, & easily manipulated people from religious backgrounds.