On this week’s podcast, David and I talked through what types of election results are possible for both parties given just a small “normal” polling error favoring either party. In the FiftyPlusOne.news forecast, a normal miss in Republicans’ favor leaves Democrats stuck at 50 seats, and a miss in Democrats’ favor puts 54 or more on the table.
But if we use just the polling average, instead of the full prediction model, and consider that at 18 days before the election the polls could still shift in either direction, the map expands even more. A typical miss — 3.7 percentage points on average across the country, plus individual state-level noise — in either direction takes Democrats anywhere from 47 to 56 seats.
In this short Friday Chart of the Week, I pulled the public polls of every competitive Senate race since 2000 from the FiftyPlusOne.news polling database and compared the polling averages 18 days before Election Day with actual election results. If polls are off by even a point mo…