I don't know if it's nerdy or cynical, but I look very carefully at who pays for ads on TV and in the mail. Also, I sometimes look up PACs that text. One had collected $100k but distributed only $1k to 1 candidate.

In Calif. "So how do we find out more about who’s paying for them?" #LAist
https://laist.com/brief/news/politics/political-mailers-campaign-spending