Strange that calls for contributions are being made, after the announcement early in 2015 by the Koch Brothers about their spending plans for the next two years : 889 million dollars. That's a lot of money to mooch. Just think of all the jobs it could create ... legitimate jobs ... as long as those jobs do not involve exempt-from-the-Do-Not-Call-List telephone calls.
Since scammers can spoof the telephone numbers of legitimate political fund raisers, I suggest all supporters never contribute to any call, and that they only contribute by mail. Even better, hang up quickly and then block the calls.