Why do the "Patriotic Millionaires" need donations?

The Donate button leads to a donation page where these patriotic millionaires are happy to take your credit card billing information or allow you to pay via PayPal to support their efforts.

So how patriotic are these millionaires?

Not so patriotic that they will voluntarily pay extra taxes to the government, and not so patriotic that they will pay for their own campaign to raise other people’s taxes.