I think that we should outlaw anything but anonymous contributions. Support who you want completely based upon who you believe represents "the way it should be", maybe they'll get elected, but if you tell them you paid money to them, you go to prison/get fined huge/have your business shut down/whatever. If the politician is implicated in the knowledge without reporting it, then they get the above repercussions as well. Per plate dinners and trips to Bermuda can go the way of the dodo.
I am quite sure that anonymous donation proxies could be set up easily. I just don't think that politicians would ever vote this into place.
Remove the money from the equation, at least from the public political contributions, and maybe legislation will compete a little more on merit. Making your opinions, wants, and desires known is very relevant, making your personal financial contribution(s) known is not.