A big reason why Trump has a small but meaningful chance of winning reelection comes down to the advantage that Republicans currently have in the Electoral College. Trump has only a 3 in 100 chance of winning the national popular vote, according to our forecast, but he has about a 10 in 100 chance of winning the election. That means in most scenarios where Trump wins, he loses the popular vote.

And this disconnect exists because the battleground states tend to lean a little bit to the right of the country as a whole. You can see this by looking at the FiveThirtyEight forecast’s average margins for each state:

The rightward tilt of the Electoral College can be defined by how the tipping-point state votes compared with the nation. This year, the most likely tipping point is Pennsylvania, which we currently forecast to vote about 3 points more Republican than the national popular vote.

We can sum up the GOP’s advantage another way, too. If you take all the states that we forecast to vote to the right of the country, they add up to 286 electoral votes, while the states to the left total only 252. So if the presidential contest proves to be closer than our average forecast expects, you can see why Trump could manage to pick off some of the swing states where Biden has a narrower advantage. Still, remember that one party’s edge in the Electoral College isn’t permanent — it has bounced back and forth over time and could help Democrats more in future elections.