People get together and they donate to organizations so that a pile of money can be used to create a message that can be broadcast en masse as part of the a political campaign. They are the lifeblood of Hillary Clinton campaign, the banks and all these big time rich people from Hollywood and Silicon Valley are the mother's milk of her campaign. They are the money. She just doesn't want Donald Trump to have it or any other Republican to have it or any average citizen to be able to bundle his money with other people's money and create an ad or a campaign.