His numbers started going down when it was clear the Wright story wasn’t going away and was making SD nervous. He needed a reason to come out and denounce the guy because his first speech didn’t do the job. He couldn’t just come out of the blue and suddenly denounce him when the man hadn’t publicly said anything else. He had absolutely no other choice.
The number decline got precipitous after Wright’s latest appearances. If Wright had stayed in the background the issue would have faded.