What would happen to campaign contributions if the payback dried up?

America

Hillary Clinton already has a campaign war chest reportedly exceeding $2.5 Billion. Her opponents in both parties are attempting to match it.

Click to read the short story "Lights Out"

Despite the obscenity of campaign spending for elected office in America, there doesn't appear to be any political will to rein it in. Why? Could it be that the prize is simply too great to scrimp on spending to achieve it? 

What if instead of treating the illness - campaign spending - we focused on reducing the value of elected office?

Lights Out is a short story, a dream of mine, in which campaign contributors learn that the return on investment for campaign contributions is suddenly diminished.

Would campaign finance reform be a mute topic?