Reply #30: My guess is that it's part of the vetting process.

[Sirveri]

I don't think any candidate is allowed to run if they can't prove that they're elligible for the position.

I have to provide proof that I'm legally entitled to work in the US when I apply for jobs too. So my guess is that every single candidate submitted it when they announced their primary bid.

Do I have proof, no, not really, but it makes sense to me. The fact that some people are trying to use it to bash Obama isn't much of a surprise either. They'll bash him for anything that's remotely possible.