Tenn. Code § 2-10-133
A candidate or political campaign committee, in soliciting and receiving a contribution from a person, shall not utilize pre-checked or pre-marked boxes in a solicitation authorizing or requiring continuing future contributions to that candidate or committee from the credit card or another form of payment provided by the person from whom a contribution is requested. Such a request for a continuing future contribution from a potential contributor must be accepted and acknowledged in writing by the potential contributor in clear and precise language evidencing the intent of the contributor to authorize a continuing contribution. Such continuing contributions must not exceed the contribution limits established in part 3 of this chapter.
T.C.A. § 2-10-133