Nonetheless, Biden’s standing is considerably stronger than Clinton’s at the end of the 2016 race. His lead is larger than Clinton’s in every battleground state, and more than double her lead nationally. Our model forecasts Biden to win the popular vote by 8 percentage points,1 more than twice Clinton’s projected margin at the end of 2016.
Indeed, some of the dynamics that allowed Trump to prevail in 2016 wouldn’t seem to exist this year. There are considerably fewer undecided voters in this race — just 4.8 percent of voters say they’re undecided or plan to vote for third-party candidates, as compared to 12.5 percent at the end of 2016. And the polls have been considerably more stable this year than they were four years ago. Finally, unlike the “Comey letter” in the closing days of the campaign four years ago — when then-FBI Director James Comey told Congress that new evidence had turned up pertinent to the investigation into the private email server that Clinton used as secretary of state — there’s been no major development in the final 10 days to further shake up the race.
Now, there are also some sources of error that weren’t as relevant four years ago. The big surge in early and mail voting — around 100 million people have already voted! — could present challenges to pollsters, for instance. Still, even making what we think are fairly conservative assumptions, our final forecast has Biden with an 89 percent chance of winning the Electoral College, as compared to a 10 percent chance for Trump.