One of the greatest lessons of 2016 is that polling can suffer from major flaws, especially when measuring support for and against an outsider candidate like President Donald Trump. Polls generally have had a good track record of predicting the outcomes of elections, but anyone who doubts them today has good reason to do so.
When it came to the national polls they did come close to estimating the popular vote in 2016, but state polls is where things broke down. State polls were off by roughly five percentage points in 2016. Needless to say, with our electoral colleges system the national polling is practically irrelevant, while the state polls, particularly in key swing states, are the most important.
After their embarrassing failures in 2016, the pollsters acknowledged that their samples were biased and understated the support Trump would receive from non-college educated whites, which propelled him to victory. So after four long years of being able to rework their polling methodologies, by 2020 they were able to give forecasting the election results another shot….. and were off by even more than in 2016.
HotAir’s John Sexton put together a compilation of the major polling failures this election cycle.
Example 1: Maine’s Senate Race
Not a single poll predicted that Susan Collins, who won her race, would win her race. Quinnipiac predicted that Collins would lose by 12 points, when she actually won by 8.8, for an incredible 20.8 point margin of error.
Example 2: Florida
The average poll predicted Biden would carry the state by 0.9 points, while Trump won it by 3.4. The only polls that predicted a Trump victory were from pollsters that are often accused of Republican bias, and even they understated how much Trump would win by.
Example 3: Wisconsin
The average poll had Bidden up 6.7 points in Wisconsin, which he carried by 0.7 points. This state is likely to be the subject of a recount request.
And Some Notable Other Cases…
Even polls that greatly favored Republicans massively understated their support. Mitch McConnell polled 9 points ahead of his opponent who he defeated by over a 20 points margin, and Joni Ernst only polled 1.4. points above her opponent, but won by 6.6.
While the national polls for the presidential race aren’t as important as the state polls for reasons previously explained, they too were more inaccurate than in 2016. In 2016 the RealClearPolitics average had Hillary Clinton ahead by 3.2 points while she won the popular vote by 2.1, this cycle the polls had Biden leading Trump by 7.2 points (51.2% to 44%), Biden is leading 50.5% to 47.8% as of writing, for a 2.7 point lead, and margin of error of 4.5, more than twice as large.