Many religious people vote Republican because of social issues, particularly abortion. Frequently they also support the economic policies to the Republicans even though these are at odds with their faith. This is a huge mistake.
Many Republicans very much favor abortion and are against the religious voters on many other social issues. If religious voters express support for Republican economic policies the Republicans will argue that we have to compromise to win, and since we all agree on economic issues, abortion and the social issues should be sacrificed. This is not a theoretical problem, it has frequently happened in the past.
Do Not Give Away What You are trading