Read other letters about this article
Donors would require some sort of receipt from the FEC to demonstrate where their money has gone, or else the FEC itself would be open to charges of fraud in their allocation of money. Then all you’d have to do is show your candidate the receipt and voila, influence obtained (and without the inconvenience of public disclosure).
Even if it did work, all it means is that candidates would have to become more ideologically pure so that donors could be more certain that their money will bring about the changes they desire. Incrementally beneficial or narrowly targeted legislation would be too subtle. To attract money, candidates would have to pander even harder than they are doing now. This doesn't mean responsive to constituents - it means slavishly obedient to phantom masters.
Every time an effort is made to reform campaign financing, the system gets worse – campaigns get uglier, incumbents and the two big parties reap most of the advantages. Leave bad enough alone.