Actually, we don’t need to speculate here. There are many, less corrupt, developed countries where lobbying isn't as deeply intertwined with political money as US, and we can look at them to see what the substitute is. For example in France, corporate political donations are simply banned, and campaigns are publicly funded. In Nordic countries like Sweden, the substitute is institutionalized consultation. Of course corruption exists, but how deep is what practically matters here! So the answer is, access is granted based on your relevance to the issue, not by how much money you can spend and people would be voting for the government that can do this better when they see their voices are actually heard.