Population shifts, demographics favoring Republicans in 2024 presidential race

Mar. 30—An analysis of the latest census data and population shifts by Franklin & Marshall's Center for Opinion Research Executive Director Berwood Yost portends trouble in Pennsylvania for President Joe Biden in his reelection bid versus former President Donald Trump.

The aggregate population of the counties that voted for Donald Trump in 2020 increased by roughly 4,500 people, while the aggregate population in the 13 counties that supported President Biden declined by more than 45,000 people, Yost said, in a blog post.

The main reason for the larger population decline in Biden counties is that Allegheny County and Philadelphia had the largest net population losses, losing approximately 26,000 and 53,000 residents, respectively. Chester and Montgomery counties, despite having the largest population gains in the state, with close to 15,000 and 12,000 more residents in 2023, could not offset the large losses in the state's two major urban centers.

The Pennsylvania counties that Biden won in 2020 represent a majority of the state's population (55.6 percent) and registered voters (56.9 percent). The new population estimates do nothing to change that, Yost said.

Still, the population changes that have taken place since 2020 increase the chances that this election will once again be closely contested, in part because the Trump-won counties are so uncompetitive, said Yost. "In 2020, the median margin of victory for Trump was about 40 points in the 54 counties he carried, compared to a median margin of victory for President Biden of 8 points in the counties he won.

"President Biden's poor job approval ratings suggest that he could lose by larger margins in the 2020 Trump counties while his margins narrow in the places he won. His poor job approval ratings alone pose a challenge to his reelection," Yost said. "The population changes that have happened in the state since 2020 do nothing to make this challenge less difficult."