By the end of this week, the Cook Political Report will be rating about eight Democratic open seats as either Lean or Likely Republican, about 45 in the Toss Up column and 30 more in the Lean Democratic column, bringing the total number of vulnerable Democratic seats to about 80. To be clear, Democrats are not going to lose 80 seats. In the 26 years of the Cook Political Report, no party has ever even come close to winning every single competitive House race. But it would be reasonable to assume that each of the Democrat-held seats in the Lean or Likely Republican column will be won by the GOP and that the overwhelming majority of Toss Up seats will go Republican. In addition, in this kind of a wave year, it's reasonable to assume that Democrats will lose some of the currently Lean Democratic seats, those races where Democrats are currently ahead but have far less than insurmountable leads.