Who contributed to you is among the considerations, but not the only one. After that you'd probably put people who've given money. I didn't even hear from a PAC just before a committee vote or something like that. I think what access is related more to is how skilled and cordial someone is. I have some very close relationships with lobbyists.
Some senators approach the matter differently than others.
And it's only fair that I tell you that up front. On the other hand, it's fair to say that those who contribute may have more ready access and may at least be able to present their arguments with you whether you agree with them or not. For one prominent lawmaker, the problem wasn't extracting money from contributors - but giving it back. I was fortunate in that I was able to raise all the money I needed in the year preceding the election year. In 1988, I stopped raising money in March and returned hundreds of contributions.