Yes.
>Can I spend $10 million creating the youtube video, if I have that much money as a private individual?
Yes. However, if it turns out that those ten million were gathered from other friends, explicitly in the goal to make this video without disclosing your donors or ignoring the caps, you should be fined and be made unelectable for multiple years.
>Can I organize a group of 10 friends to each spend $1 million on the youtube video?
Not if that video is part of your campaign, because then the amount each person can donate is capped.
>Can I organize 1 million people to spend $10 each on said video?
Yes.
The only real problem in those four is the third. Because it is infinitely easier to organize only ten friends to donate one million to your campaign than to organize one million people, especially if you're already in the category of people that can afford to blow ten millions like that.
As a bonus, at least having one million people donating to you demonstrates that you actually have people following you.