Pennsylvania: The Ultimate Swing State

A brief look at the 2024 presidential results in Pennsylvania. Plus, how three Congressional districts in PA could flip the House in 2026.

Today will be my final post about the 2024 election, and for those of you eager to look ahead rather than back, I share the sentiment. Next month’s post will be about the key Senate races of 2026, and in general, my focus will be on the midterms from here on.

But for now, we simply have to talk about Pennsylvania, and there’s a reason I saved it for last: it truly is the single most important swing state. It’s not a stretch to say that if we somehow knew at this moment which party won PA in 2028, that alone would likely be enough to know the winner of the election.

It’s remarkable how long Pennsylvania has been at the center of US politics, and how well it tends to reflect the national mood. Since 1992, it has never deviated from the nationwide popular vote in a presidential election by more than 5 points, something that only one other state (New Hampshire) can claim. True to form, last November, Pennsylvania came incredibly close to matching the national popular vote.

On top of that, Pennsylvania even ended up being 2024’s tipping-point state. Basically, if the election had been closer, let’s say with a tied popular vote and every state shifting 1.5 points towards Harris, Pennsylvania would’ve been the state that decided the winner. It was Pennsylvania that clinched Trump’s Electoral College victory, just as PA could have potentially been Harris’s 270th electoral vote if she had first won Wisconsin and Michigan.

So, you get the idea: Pennsylvania matters in a way no other state quite does. I’ll spend the first part of today’s post giving an overview of how the state flipped red last fall, and then I’ll look at the major role Pennsylvania will play in determining control of the House in the 2026 midterms. If you’ve had enough reading about 2024, feel free to skip to the bottom of this post.

The first thing to know from last November is that Trump won Pennsylvania by 1.7 points, making it the reddest of the three northern swing states. From 2020 to 2024, PA swung almost exactly 3 points towards Trump, putting it right in the middle of the swing states in terms of their shifts (Arizona, Michigan, and Nevada swung to Trump by more, while Georgia, North Carolina, and Wisconsin swung to him by less).

Compared to the other swing states, I think Pennsylvania sort of defies any single narrative. Part of that is because PA is arguably the most complex of the swing states, being a mix of different regional and political cultures. The state is a hybrid of the Northeast, Appalachia, and the Midwest, and at first, I was tempted to simply go through the 2024 results in each region, but that would only make it harder to see the bigger picture.

Instead, I think we can get at the story of PA in 2024 with a map that divides the state into a western and eastern section, each of which contains roughly half of the state’s population. We’ll pretend these are two separate states (and honestly, they almost could be), with the red half named West Pennsylvania and the blue half named East Pennsylvania.

By the way, I promise this is my last swing state map for a long, long time.

If it comes as a surprise that nearly half of PA lives in those blue counties, keep in mind that fully a third of the state lives in southeast PA (Philly plus its four surrounding suburban counties). From there, adding the Lehigh Valley and northeast PA gets you to a little under 50%.

Just to give a quick sense of how demographically distinct these two halves are, eastern Pennsylvania is roughly 61% white and 39% non-white, while western PA is about 84% white, according to the latest Census Bureau estimates. As the map makes clear, East PA is the much denser half of the state, being home to Philadelphia, Allentown, Reading, and Scranton, among other cities. Although West PA does contain Pittsburgh, Lancaster, Harrisburg, Erie, and York, these are smaller cities, and even when combined, they come nowhere close to matching the population of Philly (which also has more extensive suburbs). This helps explain why it takes so much of PA’s western land mass just to reach about half of the population.

To understand how Pennsylvania flipped red in 2024, we first have to realize that it has very little to do with West PA. In 2020, Trump won western PA by 18 points, and in 2024, he won it by 19 points, a shift barely worth mentioning. I was surprised to see this at first, but it does make a lot of sense. In an election defined by racial depolarization, Trump had little to gain in western PA, which is overwhelmingly white. And in two key parts of West PA, the Pittsburgh and Harrisburg/Lancaster area, Harris generally matched Biden’s margins from 2020, even outperforming him at times.

East PA, however, is another story entirely. This half of the state shifted meaningfully towards Trump, and its demographic profile (diverse, but home to multiple counties with lower levels of educational attainment) meant that Harris had significant room to fall compared to past Democrats. Notably, most of the state’s Hispanic population lives in East PA, and almost no other group of voters swung more to Trump last November.

But on top of that, Harris fell short of Biden even in the suburbs of eastern PA, which came as a real surprise. For example, Harris won Montgomery County, the third-most populated county in the state and the epitome of suburban southeast PA, by a little under 23 points, down from Biden’s 26-point win in 2020. That may not sound like much, but a reasonable benchmark going into the election was that Harris would at least match Biden’s margins in affluent, highly-educated counties like Montgomery. Harris’s weaker showing in Chester County was also genuinely surprising, as was Trump flipping Bucks County by the thinnest margin.

Of course, we’ve got to talk about Philly. The city’s shift away from Harris could easily be an entire post, but the map below gets the basic point across. As you may have guessed, the precincts that swung the most towards Trump from 2020 to 2024 are in the darkest shade of red. Northeast Philly really stands out here; this diverse, working-class section of the city has a mix of Hispanic, Black, and Asian neighborhoods. Even Biden, despite winning PA in 2020, did worse in this part of Philly than Clinton had in 2016, a reminder that Democratic erosion with the non-white working class predates 2024.

This is a screenshot from the 2024 election map that was recently released by The New York Times. The map, which can be seen here, is definitely worth checking out.

It might be tempting to think that Philly was the main reason PA flipped red, but keep in mind, the city only cast about 10% of the statewide vote last fall. Even if Harris had somehow matched Obama’s 2012 winning margin in Philly (the largest in its history), that alone would not have changed the result in PA.

Looking further north in East PA, we come to Scranton, Wilkes-Barre, and the Poconos, all of which shifted quite a bit to Trump in 2024. This, at least, did not come as too much of a surprise. Whether it was due to his Scranton roots, Catholicism, or working-class upbringing, Biden did fairly well in northeastern PA back in 2020. This region had moved sharply towards Trump in 2016, and Biden’s ability to claw back ground here was a key reason he flipped the state blue in 2020, but Harris did not even quite match Clinton’s 2016 margins. Harris’s losses in northeast Pennsylvania are, in my mind, among the most important shifts seen in PA last fall.

Overall, eastern PA went from Biden +22 in 2020 to Harris +17.5 in 2024, which tells you almost everything you need to know about why PA flipped red. As mentioned earlier, western PA only swung to Trump by a single point, a nominal shift. Given the 2024 results nationwide, in which diverse, urban areas generally moved most dramatically towards Trump, this east-west split in PA is not surprising. Simply put, eastern PA was the part of the state where the new political alignment, which has inverted the traditional voting patterns of class and race, was bound to hurt Harris the most.

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Pennsylvania in 2026

Even though Pennsylvania doesn’t have a Senate race next year, and probably won’t have much of a governor’s race (I doubt Shapiro will draw a particularly strong challenger), the state will feature three competitive House races next fall. By themselves, these three House races could flip control of the chamber. A fourth House seat, which I’ll mention at the very end, could also be worth watching. In rough order of competitiveness:

• Pennsylvania’s 7th district: If someone asked me which of our 435 House districts best captures the country as a whole, PA’s 7th would be at the top of my mind. This Lehigh Valley district, home to Allentown and Bethlehem, is demographically comparable to the nation, and is highly competitive. Last fall, Democrat Susan Wild, who first won the seat in 2018, lost by a point to Republican Ryan Mackenzie. Regardless of who Democrats nominate next year, this district could end up having the closest House race in PA in 2026, and is arguably the most likely to flip.

• Pennsylvania’s 10th district: This Harrisburg-centric district was newly drawn in 2018, when Pennsylvania’s Supreme Court struck down the state’s gerrymandered Congressional map. Since then, incumbent Scott Perry, a Republican initially elected to a much redder district, has seen a few close races, and he won by just a little over a point last fall. The 10th district, which extends from Harrisburg to the areas around Carlisle and York, has clearly been trending towards Democrats in recent years. Harris did relatively well in this part of the state, even as much of the rest of PA swung against her. Expect a highly contested race, especially if Democrats once again nominate Janelle Stelson, who gave Perry his most narrow win yet last fall.

• Pennsylvania’s 8th district: Directly north of the 7th, this district includes Scranton, Wilkes-Barre, Hazleton, and much of the Poconos. This part of the state was historically Democratic, but has become significantly redder since 2016. The 8th district is currently a bit more Republican than either the 7th or 10th, and its former representative, Democrat Matt Cartwright, was able to hold onto the seat longer than might have been expected. Having represented northeast PA in Congress for over a decade, Cartwright would very likely be the strongest Democratic nominee next year, but if he decides not to run for his old seat, the 8th would only be somewhat likely to flip; its demographic/educational profile makes it a challenge for Democrats.

• Pennsylvania’s 1st district: This House seat, located primarily in Bucks County, is represented by Brian Fitzpatrick. He is arguably the most moderate Republican member of the House, and has overperformed in all of his elections, often winning by double digits. He did have a close race in 2018, but 2026 would have to be an exceptionally blue midterm for Fitzpatrick to be in real danger. At this early stage, my best guess is that Fitzpatrick will win by single digits next year, closer than what he’s used to. Still, the seat should be seen as potentially competitive, and I assume it will receive much more attention in 2026 than it has in the last few election cycles.