All night we'll be digging into data from some of the battlegrounds and key races of this election.

For a deep dive into all of that, we're joined now by our Lisa Desjardin over at the PBS News Super Screen.

All right, Lisa, so let's start with the big state. Everyone is watching tonight.

Pennsylvania. What counties are you tracking?

I'm sad we have to pick just a couple to highlight, but it is election day, so it's all about choices. And let's start here in Philadelphia, the most important county for Democrats.

Let me show you what happened here between 2016 and 2020.

Hillary Clinton, 83%, but that actually went down for Joe Biden.

81%. That's great in any county, but when it's your biggest county,

this is a place where Kamala Harris needs to do more like Hillary Clinton than like Joe Biden.

Let's look at somewhere that the Trump campaign is paying attention to.

This is Berks County. What's there? Reading. This is where Donald Trump ended, had his last rally in Pennsylvania last night,

a place known in love by the Desjardin family. And I want to show you what's going on here, why the margins

in Berks County matter. Donald Trump actually had about the same margin between 2016 and 2020.

But look at this. Joe Biden gained percentage in this county. Also paying close attention to

Brooks County because its population, 25 percent Hispanic, including many Puerto Ricans. You want to see

there's any effect from those remarks from the Trump rally earlier a couple weeks ago.

Lisa, we know we could have a long night ahead. So what are some of the places you're tracking

that could give us some of the earliest look at what's to follow?

Georgia is one of the states we expect to hear from first, especially

these some of these counties around Atlanta. Let's talk about Gwinnett County. This is a place

that used to be read now has voted more blue. Also Cherokee County, this is somewhere we're

going to talk a lot about not just who wins these counties again, but the margins. This is

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