So, why do GOP candidates go all God-talk on the trail?

Because that’s the base they have cultured, and their base wants moar God:

Emphasizing a personal approach, GOP Senate hopeful Mark Harris converts voters one at a time

[…]

Republican Dorothy Cherry, a 74-year-old retiree from Stedman, who heard Harris preach years ago at her church, came to shake his hand. “I know he’s a Christian,” she said later, when asked why she was supporting him. “My first thing is he has the qualities (needed), he has a good reputation and he believes in God. I just think this country needs God in their lives.”

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