I believe that a group of people have every right to pool their resources together to create videos, commercials, books, posters etc for their common interest. Whether they choose to do so as a corporation (like the ACLU does) or as a concerned group of citizens with a voice, the right to free speech is a sacred foundation of our constitution.
I personally feel trying to say corporations are not a person will not do anything, since the constitution allows free speech in general, not just of individuals. Or else the government could ban people from joining together to create speech. (like mothers against drunk driving). To me it seems obvious speech in general should be protected, not just from individuals. Banning speech because of its perceived negative consequences is censorship. I am wholly against censorship, especially if it is government-sponsored and especially if it is censorship of political speech.
I do agree however, that money plays far too large a role in politics. Its one of the major faults of capitalism. The needs of those with the most money is met far more than the needs of people with you know, actual needs. And usually the needs of those with money is to make more money and protect the money they have, even if it against the interest of the common man. As I have said before, I really am at a loss as to how to curtail the power of the wealthy, especially in a capitalist society like ours.