FiveThirtyEight is a website that was founded as a poll aggregator and now covers news on a variety of topics with a focus on statistics, polling, economics, and related subjects. It has had notable forecast successes in the past and had among the highest likelihoods for Donald Trump among several forecasters in the 2016 election. It continues to provide polling averages as well as a 2020 election forecast.
Trump's election in 2016 was a surprise to most forecasters, in part due to polling error that showed Hillary Clinton as having a larger level of support than actually materialized in the election. One hypothesized contributor to polling error in the 2020 election is the "shy Trump voter" effect, in which Trump voters do not tell others how they intend to vote for fear of political backlash. The existence of this effect is still under debate; FiveThirtyEight's team discussed this possibility on its Politics podcast and generally considered it unlikely.