How hard is it to regulate funding for NFPs?

I can’t stand behind a mass protest, without a goal. I can however, stand behind the historical representation of a mass social consciousness. Which, a protest like Occupy Wall St., clearly is.
I’ve been considering some potential goals that seem fitting for these protests, that I would like to see them ask for.
Whether they would all agree, is another thing.
One goal I could stand behind, involves getting rid of Corporate Lobbying altogether. This seems to be in line with what I believe Occupy Wall St. is all about, so, I’m trying to think this through.
I would not think it democratic to stop Not-For-Profit Lobbyist groups, like Human Rights Campaign, AARP, or PETA (whether I agree with them or not) from lobbying, but I do think we should stop these groups from accepting corporate funding. I also think we should outlaw any Corporate funding/financing of campaigns and lobbying outside of NFPs, altogether.
So, why can’t we make it illegal for NFPs to accept corporate funding, and then make lobbying illegal, for all but NFPs?
Of course, this would require regulation of whatever funding there is for NFPs, and I realize that would be somewhat complicated/difficult. It would also create some jobs and
it would also likely mean that the government would have to be allowed to keep track of Corporate money, once a particular Corp. reaches some prefixed net worth; or so I’d imagine.
This is tricky. Of course, the Tea Party and much of the right hate it…I get all that. I just don’t agree. I’m not posting this so that we can argue over whether we should call a duck, a duck, or not.
Please use restraint, and agree to disagree. In a way, I’m asking this on behalf of a general consciousness in the world, that is acknowledging that Capitalism, in its current state, has trumped Democracy. This might sound great to you, if you believe that people should be allowed to use wealth to accumulate and exercise power, but many, including myself, do not. If you don’t agree that this is so, please refrain from discussing that here.
So, I’m not asking for the expression of the opposition to this idea. I think it is clear from these protests that more than enough people want this to be seriously considered. Yes, I realize that doesn’t necessarily mean it’s true.
I’m more so looking for the iconoclasts in the room to consider and discuss the potential trouble with legislating these proposed regulations upon Lobbying, and corporate funding. That is, assuming it would pass.