JOHN,
We always knew that this campaign would get nasty in the final stretch. My opponent has run an especially weak campaign--people from around the district have asked "Where's Chad?" when we're out in the field.
We now have our answer. He was apparently meeting in back rooms with GOP power players begging them to bail out his failing campaign, and they responded with the same dog-whistle playbook they always trot out. You can see a little taste in the screenshot below from Chad's first mailer.