There appears to me a clear disdain for people who attempt to "buy elections", or for those who choose to spend their money on candidates who mirror their ideological views. Are these views on wealth damaging to the American idea of Democracy? Or are they perhaps an insight into how people want to regulate to make it equal across the country?
I would oppose the idea of preventing interested parties from donating, regardless of the amount, based on my perception that it wouldn't be what America is today. This country has been the champion for capitalist ideals, ever since our successful bid against the Communist Soviet Union. We've spread our message across the world, even influencing (or threatening?) many of our allies to adapt similar stances to our own. To regulate private funding, we regulate the right to voice our political views in the form of financial support. Would this not create precedent to then regulate more, in order to create an "equal" and "fair" playing field? Is our capitalist society really "equal" and "fair"? I'd say no, and I would prefer to keep it that way. We need a way to incentivize people to rise above and create better; not to settle for mediocrity. The only regulation I would propose would to make all contributions visible and available to the public. If a wealthy donor chooses to contribute, let the world know, and don't attempt to obfuscate the knowledge.
I'm sure the total amount spent on campaigns has an effect on the victor, but it certainly isn't bulletproof. Findings by Jeffery Milo in his Campaign Finance article (http://www.econlib.org/library/Enc/CampaignFinance.html) looked into this very matter. He points out the total spent by Jon Corzine in his 2000 senate bid to be sixty million, but still trailed against his fellow democrats in the house, while up against a weak Republican opponent. Money buys votes, but it doesn't sway elections, and hopefully not informed voters.
Spending regulation may happen in our lifetime, but you cannot regulate the voters whose political knowledge does not extent past television, radio, and facebook.