Honestly, I think it's more than a little silly, and lends credence to the view of Ron Paul supporters as fanatics in a cult of personality. Surely we don't all like her music that much! I bet she's a great person, but her music is not to my tastes, so why should I buy it? If my goal is to spend my money supporting liberty, there are more effective things to do.
If Kelly Clarkson supports Ron Paul I am glad for it, but I'm not going to be complicit in essentially bribing her to maintain that support. If she was going to withdraw support in the face of criticism, then what good was her support in the first place? And now we may never know how strong her support really is.
But anyway, if you LIKE her stuff, that's something else, and I really have nothing but best wishes for her.
I like the idea of bribing her to maintain that support. Unfortunately, buying her CD is an inefficient bribe, as most of the money goes to the label. But we're really just showing that Ron Paul Supporters Are Mighty. Which is the point. We're getting press, good press, in sections of the newspaper where we usually don't (entertainment, economics).