The short answer is I don’t know yet. But I’m exploring the question.
I’ll start with political spending by “business interests”, a convenient category that includes rich people, corporations, non-corporate businesses, business associations, and industry groups. If spending by business interests influenced US elections and legislation in a major way, one would expect the US to do well in the World Bank’s Ease of Doing Business rankings. And it does okay:
The Scandinavian countries all have strict limits on political spending, yet they seem to be at least as friendly to business as the US. Something to ponder and research further.
In the meantime, a few thoughts on the influence of lobbyists and what to do about it. Policies and laws are very complex: drafting them requires a degree of expertise. Lobbyists are invaluable to legislators because they provide a lot of useful technical information - and yes, sometimes they play a major role in writing the legislation (whether they're lobbyists for the Teamsters or the Mining and Extraction Industry Council). The issue isn't to eliminate their input but to make sure other perspectives and data are also considered. That's why I think the budget for congressional aides, the Congressional Research Service, the Congressional Budget Office, and similar federal, state and local government research and analysis entities should have increased funding. Businesses should be given a fair hearing about any potential legislation that affects them - and our legislators should have access to other sources of information as well.