Well, I think that dusman agrees with this basic approach, as do you and I.
People will be registering to pledge. But the way dusman sees it happening is like this:
Person enters, only, their email address. And then hits a button.
Cannot be simpler.
Then the website sends an email to the email address. That email thanks them and automatically assigns them a username and a password.
Tells them about the site, tells them the benefit of full registration.
If they want to complete the full registration, they can. If they don't, they don't have to.
But they are in the system, and their pledge will be counted, just by entering in their email, and clicking a button, which could say "pledge".
I'm currently looking at widgets. Ron Paul supporters can grab the code, with the simple "sign up to the email list" code (we're calling it pledging) and paste that code anywhere they can paste code.
People could simply enter their email and hit "pledge" whereever they see the code on the internet. They wouldn't even have to go to the website.