Very interesting read. Thank you for linking it. It has significantly altered my perception of the Citizens United issue. I see now that there's no simple way to balance campaign finance reform against freedom of speech.
Edit: Perhaps instead of focusing on campaign finance reform, we should focus on polling reform, and expanding the house? If we used a better polling system, e.g. candidate ranking, and increased the number of representatives, then it would be much more costly to buy a majority.
Big money will remain in politics as long as there is big money in politics. That is, USA federal government spends many billions of dollars every day. Lots of people have noticed, and invested accordingly in political influence. The only way to change this is to spend much less. One option for that would be to break up the union into many smaller units who would levy taxes and spend money independently. It wouldn't be such a prize to serve as e.g. chairman of the senate finance committee in such a government, so there would be far less money involved in elections for that position.
Edit: Perhaps instead of focusing on campaign finance reform, we should focus on polling reform, and expanding the house? If we used a better polling system, e.g. candidate ranking, and increased the number of representatives, then it would be much more costly to buy a majority.