As I understand it, the donation is not the price of legislation, it's the price to get your foot in the door for additional lobbying efforts later.
If a lobbyist connected to a donor requests a meeting, they get it, and if the lobbyist can then make a convincing enough case (preferably legally but sometimes otherwise) they can get action in their favor.
When you think of US politicians: think of the guy who owns the biggest used car dealership in Podunkville, Midwest.
That's your average US politician. Generally: the scummiest, griftiest jerk who happened to get lucky. Generally by inheritance as building the business takes too much energy to screw around with national politics. Not somebody smart. Not somebody moral. Think SBF but no education and knowledge whatsoever.
Mike Gallagher: $6000
Marco Rubio: $2500
Haley Stevens: $2000
Carlos Gimenez: $5000
Darin LaHood: $7000
Andy Barr: $2000
Ashley Hinson: $10000
Total: $34500
[0] https://www.opensecrets.org/political-action-committees-pacs...