[konaice]

All you need do is have Florida and New York cross check the ID used to apply for voter cards. (All done electroniclly of course).

If I apply for a Driver's license in Colorado, I have to surrender my New York License. Same could be true for voter cards.

[DefCon]

"..Florida and New York cross check the ID ..."
- - -
And cross check it with Texas, and Arkansas, and California, and Alaska, etc., etc.
It might be ISSUED by the state of residence,
but it must be VERIFIED on a national level.
And THAT, my friend, is what one typically calls a NATIONAL ID.