Curious

I don’t understand why a chuch can face penalties for publicly endorsing a politician, but politicians can use their religion to create policy, decisions, or overturn decisions.

From the NYTimes:

Organizations like Americans United for Separation of Church and State have made a show of reporting churches to the I.R.S. to deter transgressors.

Is it because churches are nonprofit and candidates are not? Do candidates ever receive deductible contributions for anything?