Harry Enten: “Let’s state it up front: winning the popular vote means nothing in and of itself. You only become president if you win the Electoral College. That said, the national polling matters a lot. We have a ton of it, unlike in a number of swing states. It’s more accurate than the state polling on average. Most importantly, we have a fairly good idea of what Biden’s margin needs to be nationally in order to win in the Electoral College. Last week, I outlined how Biden’s margin in the pivotal Electoral College states was narrower than in the popular vote. That’s still true today and will almost certainly be true through the election.”

“There is a limit, however, to the extent to which Biden can win in the popular vote without also taking an Electoral College majority. The nation, after all, is made up of the states that also make up the Electoral College. If the margins move in the swing states, then they’re very likely to move nationally as well. If Biden wins by more than 5 points nationally, he’s almost certainly going to win enough electoral votes to get to at least 270 and take the Electoral College. There’s simply little record of a difference between the margin in the key swing states and the national vote being greater than 5 points. If Biden wins by somewhere between 3 and 5 points nationally, he’ll be the clear favorite in the Electoral College, even if there is some non-negligible chance Trump could emerge victorious. Biden’s national advantage right now is clearly outside this 5-point window. There would need to be a polling miss for Trump to have a realistic shot in the Electoral College. A 2- or 3-point miss in the national polls would be far from unheard of, but it’s not as likely as you might think, at least in comparison to state polling.”