It is a bit of a stretch. In large measure because of the ridiculous Gerry-meandering.

Right now, Congressional Democrats are up collective by +7-8 points (due to Trump). You need about +16 points to be able to take back the House.

But if Trump continues to "throw shade" at the GOP establishment and blame them for his flagging campaign, it could cause more of their base to feel cheated and disenfranchised, and ultimately not come out. Trump supporters are not a fringe element within the party; they are the party, its natural expression and logic incarnate.

It could very well potentially be a blood-bath for the GOP depending on how they handle (or mishandle) this internal friction.