Calibration!! Really?? Any software/hardware developer here worth his/her salt would agree that can't be it. Let's see what could have happened: 1) The Y axis of the screen was maladjusted 2) Touch Sensitivity of the screen was reduced due to incorrect settings 3) Touch area had hair/dust/oil on it. But if you read the voter's story it happened only for Obama's field. Don't they have independent watchdogs looking aft…
Easy explanation- the voter was lying.