Certainly, unless some effort is made at making it an issue, it will never happen.
As to this:
They would start pumping their money into state legislative elections, thereby spreading their corruption national influence into more local elections.It becomes harder to demagogue issues on the local level, because the people involved tend to be known by more of those involved. But your argument is that it would spread corruption (expanding it). Yet clearly, their corrupt influence was augmented by the move to direct elections. Unless you are saying that every time it would change from indirect to direct or vice versa it would increase the currupt influence, I fail to see how the evidence supports that view.
We put this in to minimize corruption and the influence of special interests. Instead, both increased exponentially. Removing what we put in is unlikely to cause more of an increase, and may very well help quell the tide.