I play poker with a group of guys once a month. Mostly these guys are pretty darn "liberal". Meaning that they tend to share my distrust of corporate power, but they tend, instead to trust government as a counterbalance to that power. E.g. an increase in government power is an effective means to neutralize corporate power.
I tend not to express my opinions in this group. Mainly because I'm grossly outnumbered. Any time I have tried to express my opinion, I get 3-4 people arguing over me, and I never really get to finish my thought. It's basically pointless. I don't think they're interested in listening anyway, so I just bite my tongue. It's not that these are bad guys. In fact, I really enjoy their company. They're smart and funny and (unfortunately) much better than I am at poker. But when it comes to politics, we don't see things similarly. And there doesn't seem to be much willingness on either my part or theirs to see each other's point of view.
Tonight, I managed to accidentally start a rant session when one of the guys suggested that soda should be illegal. I responded saying that I wasn't particularly fond of telling other adults what to do. I was about to say that I was totally in favor of telling kids what to do, but, predictably, I wasn't able to finish my thought while I was being told how that was wrong. I immediately shut up, because all that could happen was that tempers would flare - most likely including my own.
This eventually turned into one of the guys ranting about how bad it was that corporations bought politicians. And on that topic I couldn't have agreed more with him. The purchase of politicians is a huge problem. But it was interesting how differently he and I would approach a solution. His response was that we should demand all campaign finance be opened up completely. And in general I don't have a problem with that. But he seemed to think that it was the root cause of the problem. And there I disagree. I tend to see this as a symptom of a different problem rather than the root problem.
I think the root cause of the problem is politicians with too much power. Corporations attempting to purchase those politicians are just a symptom of that root problem. Because, of course, if you're a corporation, you don't lobby those who don't have power. There's no point. You lobby, and bribe, and attempt to influence those who have the power to make changes in your favor. If you give politicians more power - e.g. the power to regulate campaign finance, or the power to regulate financial markets, or the power to rescue GM - what you'll end up with is *more* attempts by those with money to purchase those with the power. You'll end up stoking the problem that you're trying to solve.
I imagine my friend's response to be that we need to elect the "right" people so that they will stand up to this corporate influence. And maybe that'd work. The problem is that the people who are most likely to win an election are the ones who are the most duplicitous - the ones who can promise everything to everyone, knowing that they can't keep those promises. The winners in politics are very rarely - in fact almost never - the "right" people. Politics rewards people who are best at being two-faced. As a result relying on electing the right people seems unlikely to improve anything.
IMHO, the way to remove the negative influence of corporations purchasing politicians is to reduce the power of the politicians. Reduce their regulatory authority. Make it harder for politicians to create laws and regulations. If the politicians don't have power, corporations will not be interested in influencing them.
There are, of course, two problems with this answer. First, you have to elect politicians who's goal it would be to reduce their own power. What incentive will such politicians have? Once they're elected they will face a set of incentives that pushes them towards increasing their power. Put another way, my solution also requires electing the "right" people. Which I've already mentioned is pretty unlikely. Still my "right" people are fundamentally different than my friend's "right" people. My right people would go in with the goal of reducing government power, while my friend's "right" people would be smart and able to gather more power so that they could put the right solutions in place to curtail corporate influence. I believe the latter to be impossible, even if the former is highly unlikely.
Second, my friend would probably respond that this would allow corporations to run amok over the public with nothing to counterbalance corporate power. At this point, we would be at a standoff. If I were able to get to this point without being shouted down and outnumbered, I suspect that I could get no further. Because I think that individuals making voluntary choices with their money would act as better regulators of corporations than a government. And I suspect that this would be a very difficult - if not impossible - topic to sway my friend's opinion.