I've always been confused about stories like this. My understanding is that companies cannot give directly to campaigns. So, can someone please ELI5 the exact mechanism by which influence is exerted in these cases? For example, if we're talking about employees of the companies giving to campaigns, they're capped at a small number of thousands of dollars per person, and it seems unlikely that a member of congress would look at the long list of donations and (consciously or subconciously) favor the company that they work for.
What are we really talking about here?