OpenSecrets.org is there for your disposal. Use it! Think about businesses you use regularly, products you buy, artists you watch or support. Chances are likely they have a profile on OpenSecrets and you can see who they support. I for one am planning to move my brokerage out of Schwab who donated overwhelming to Republican campaigns and maybe move my insurance to Progressive (not just because of the name, their employees donate significantly more to Democrats).

The weight of billionaires is behind Trump but at the end of the day money will drive his decisions. Taking money away from his donors takes money away from him.