In most states, Grinch, there is a month interlude between when registrations stop and voting begins, in order to verify registrations as being valid. Even that is becoming more difficult when the system is flooded with registrations from groups like ACORN. In Philadelphia where I live, the Voter Registration Office was flooded with 57,000 + registrations. I re-registered about 6 weeks ago to change my address. To date I still haven't received my new card. I called them and they said that it would probably take 6 to 8 weeks due to the volume of registrations that they have been receiving. So I don't really know how much verifying is being done.
Ohio decided this year to allow same day registration/voting, leaving only a week or two to do the verifying before the envelopes with the personal information on them have to be opened and separated from the enclosed anonymous ballots and counted as votes. And the Secretary of the State of Ohio really tied the hands of the local county verifiers by not giving them access to the verification tools. So the only ones that they can discount are the obvious frauds, like the ones with Disney character names. I think this is outrageous in a battleground state like Ohio where a couple thousand votes can make the difference in the national outcome.