By Jim EllisSept. 10, 2020 — With a plethora of presidential polls being released every week providing sometimes radically diverse results, it is often difficult to draw a clear picture of where the electorate is heading.
The conventional wisdom and preponderance of polling trends suggest that Joe Biden is leading the presidential race, but that President Trump is making a comeback, and the race is beginning to show some of the same characteristics found in 2016.
Three of the key states that baffled the political pollsters four years ago were Michigan, Pennsylvania, and Wisconsin. As we will remember, President Trump was expected to lose them all but scored close upset victories in each place.
The aggregate group of 2016 pollsters missed in each of the three states and the Real Clear Politics polling archives still publicly maintains all of those survey results. Therefore, we have the historical data to draw clear parallels between then and now.
In Wisconsin, 33 polls were taken during the election cycle and only one, from the Trafalgar Group at the end of the campaign season, placed Trump in front. A total of 62 polls were conducted in Pennsylvania with only three, again including a Trafalgar poll, projecting the future president into the lead. In Michigan, 42 polls were publicly released with Trump ahead in just two.
Though it is not generally statistically significant to average polling results because the polling methodologies, and certainly sample sizes, are very different, doing so does give us a guide as to the error factor that was present in 2016, and possibly a glimpse into what might exist this year.
In Wisconsin, the average Hillary Clinton lead advancing into the general election was 6.5 percentage points. With a 0.7 percent win for Trump, the overall error factor became a whopping 7.2 percent. The Pennsylvania numbers were closer but still a significant miss. Clinton’s average lead heading into Election Day was 2.1 percent and the president won there by the same 0.7 percent that he carried Wisconsin. Therefore, the Keystone State error factor was 2.8. Michigan was a similar story. Error factor: Clinton plus-3.6 percent. Trump victory margin: just 0.3. Total Michigan error factor: 3.9.