Real Clear Polling averages showed that Democrats' so-called Blue Wall had already fallen by Oct 18th, just when Gretchen Whitmer rode to the rescue with its liberal governors in tow

 Of course David Plouffe didn't see leads in the internal polling in early Oct. They were disappearing. 

RCP polling averages moved PA to Trump by Sep 30th, MI by Oct 9th, NV by Oct 12th, and WI by Oct 18th.

The Blue Wall was entirely down by Oct 18th, which would be the final outcome, despite MI and WI flipping back to Harris at the end of October.

Democrats were already dead on Oct 18th. They just didn't know it yet when they showed up at it.

 

Oct 17th

 

Oct 18th