Who will win the 2020 Democratic presidential primaries?
Starting with the Iowa caucus on February the 3rd, 2020, American voters will begin casting votes for the Democratic nominee they wish to compete President Trump. In our statistical model, we forecast which Democratic candidate will win the largest number of votes. We factor in opinion polls and betting odds in order to form a comprehensive forecast for nine of the most high-profile Democrats that have declared their candidacy for president. Our forecast automatically updates on a real-time basis as betting odds and polls change.
We currently estimate that Joe Biden will win the popular vote with an 14.2-point advantage over Bernie Sanders. Joe Biden has a 43.7% chance of winning the most votes in the 2020 Democratic primary and Bernie Sanders has a 16.3% chance.
50% vote share250
Current Biden polling advantage 14.2%
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18.9% Bernie Sanders33% Joe Biden
Mon July 22 2019
How accurate are our predictions early on?+−
We weight candidates' vote share prediction to be 90% of opinion poll averages and 10% of betting odds. We then model the probabilities of our predictions using logistic distribution and past polling error. In early October 2015, our predictions would have shown Donald Trump winning the most votes of any GOP candidate with a 27.8% share; he ultimately won with 45.0%. Hillary Clinton was predicted to win with 62.2% of the vote and Bernie Sanders 36.4%; she ultimately won with 55.2% and he with 43.1%.
Our predictions (using data available in October 2015) of 2016 primary candidates' ultimate vote share were, on average, within 8.8 points of their actual result. Each candidate's forecast correlated with the final result by r = 84.4% and r² = 71.2%, proving predictive even in early stages of the primary process.