On this day in 08, 12, 16, 20
2008 RCP average Thursday before election: Obama +5.9
- Final average: Obama +7.6
- Election result: Obama +7.3 (-0.3 vs. avg, +1.4 vs Thu)
2012 RCP average Thursday before election: Obama +0.1
- Final average: Obama +0.7
- Election result: Obama +3.9 (+3.2 vs. avg, +3.8 vs Thu)
2016 RCP average Thursday before election: Clinton +1.3
- Final average: Clinton +3.2
- Election result: Clinton +2.1 ( -1.1 vs. avg, +0.8 vs Thu)
2020 RCP average Thursday before election: Biden +7.4
Just to put the comparable values next to each other.
2008: Obama +5.9
2012: Obama +0.1
2016: Clinton +1.3
2020: Biden +7.4
As you can see the national polls were actually off by more in 2012 than they were in 2016. Of the last three elections 2012 was the biggest error in the polling average at -3.2 relative to the result. I think sometimes we forget how close that election appeared to be. In all three cases our candidate outperformed their polling average from the Thursday before the election. 2020 is not 2016. It isn't even 2012. It doesn't look anything like those elections.