Be still my beating heart!
If only such a thing were possible.
I see no reason why it wouldn't be possible to send deputized monitors to designated voting areas to check ID's and citizenship,though. In today's digitized world,there is no reason this can't be done so quickly no legitimate voter would be penalized in any way.
For emphasis,it would be helpful to park a paddy wagon outside each precinct to haul off the ones they catch trying to vote illegally.