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Democrats have voter registration advantage in four battleground states

A look at voter registrations in four key battleground states since 2016 shows how the political age divide could have real impact this fall.

WASHINGTON — Even before the COVID-19 outbreak and the economic slump, President Donald Trump faced a big challenge in his re-election effort: a changing American electorate. Young voters have been a challenge for Trump since he entered politics (he lost voters under 40 by double digits in 2016), and every year a new set of them enters the voting pool.

There are new voters of all ages every year, of course, but the biggest increase tends to be among those who turn 18 and "age into" voting. A look at voter registrations since 2016 in four key battleground states shows how the political age divide could have real impacts this fall.

Let's start with Pennsylvania, one of the three "Big Ten" conference states that put Trump over the top in the Electoral College and where Trump won by a narrow margin.

Since Election Day 2016, Pennsylvania has added 922,000 new voters to the rolls, according to data from TargetSmart, a Democratic political data company. Democrats have an edge of 132,000 over Republicans in new registrations. In addition, there are about 197,000 registered unaffiliated, that is without a political party.

That 132,000-registration edge for the Democrats is not insignificant. In 2016, Trump won Pennsylvania by less than 45,000 votes. The Democrats' new registration edge isn't definitive, of course: People don't always vote for their parties, and they can switch parties. And registered voters, whatever their parties, don't always vote.

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But the Democrats' new registrant advantage in Pennsylvania sheds light on how Trump's fight for the state may have gotten a bit harder in the last four years — particularly considering how much the president has focused on his voting base rather than working to expand his supporters.

And other states show the same trend to varying degrees.

Florida has added 2.4 million new voters since Election Day 2016, with Democrats holding an edge of 59,000 in new registrants in the two-party split, with unaffiliateds clocking in at 858,000 new registrants. Trump won Florida by a more solid 112,000 votes in 2016, but 59,000 is not an inconsequential number.

In Arizona, more than a million new voters have registered since 2016, and there, things have been a bit closer. Democrats hold only an 11,000-person edge in new registrations. In addition, there have been 355,000 unaffiliated new registrants.

And North Carolina has added 1.3 million more voters to its rolls since 2016. Democrats had an edge of more than 56,000 in new registrations, while 583,000 others registered as unaffiliated.

In state after state, the story is the same: Democrats have the high ground among new registrants. Even in states like Wisconsin and Michigan, where voters don't register with parties, data modeled from existing demographic and geographic patterns shows that Democrats hold an edge among new voters.

For Republicans and Trump, there may be some hope in the unaffiliated voter data. In every state, the number of unaffiliated new voters is higher than the Democratic advantage in new registrations.

But there's a problem with that reading of the numbers. A deeper dive into those unaffiliated registrations shows the majority of them were made up of younger voters in every state.

In Florida, 56 percent of the unaffiliated voters were under age 40. In Pennsylvania, the figure was 61 percent. In Arizona, it was 63 percent, and in North Carolina, it was 69 percent. Trump won about 37 percent of the under-40 vote in 2016.

Add it all up and the new registration numbers show an additional challenge for Trump in key battleground states. The voter pool is changing.

Are the numbers small? Yes. But four years ago, Trump won the Electoral College by winning three states, Michigan, Pennsylvania and Wisconsin, by about 78,000 votes. In other words, even numbers as small as these could end up making a big difference in November.