Reports are unclear but what I have read states that the bully wrote a personal note on the bottom of a bulk mail fundraising letter for one individual.
Having dealt with bulk mail and campaigns I know that one of the cardinal rules of the post office is to receive the bulk mail rate there can NOT be any personal notes and with the exception of of names filled in for salutary purposes ( i.e. Dear John Smith v. Dear voter) as the single exception.
So if this thug put a personal note on the bottom of a bulk mail fundraising letter he just admitted that he violated Postal rules and, by extension, has committed a federal violation.
Maybe some one in his district should contact the Postal authorities and have an investigation initiated