Here’s what pollsters think happened with 2020 election surveys

For the past six months, pollsters have investigated why surveys conducted ahead of the 2020 presidential election systematically underestimated support for Donald Trump. National polls in that election, despite generally pointing to the winner, saw the highest level of error since 1980, according to preliminary research presented Wednesday at a polling industry conference. At the state level, presidential polls understated Trump's support by about 3.3 percentage points on average, while overstating Joe Biden's support by about 1 point.