When Taylor Swift came out to endorse Vice President Kamala Harris last month, it was the Instagram post heard round the world (or at least round the TikTok FYP algorithm).

Im voting for @kamalaharris because she fights for the rights and causes I believe need a warrior to champion them, Swift wrote immediately following the first, and only, debate between Harris and former President Donald Trump . She signed her message Taylor Swift, Childless Cat Lady a knock at Republican vice presidential nominee JD Vance, who has used the term to demean women without children.

With her simultaneous endorsement of the Democrat and swipe at the Republican, Swift, at 34 arguably the most famous millennial woman in U.S. pop culture, also made herself the avatar of an ongoing shift in politics among her demographic of young women: For the past few decades, they have been tilting decidedly left.

Its popping out in the polling because its more dramatic this year than it has been in other years, said Elaine Kamarck, director of the Center for Effective Public Management at the Brookings Institution.

The Harris campaign has been assiduously courting women, and particularly young women. Harris regularly makes abortion rights a talking point in interviews and stump speeches, has embraced the meme-ification of her campaign (including Charli XCX enthusiasm and Swift-themed get-out-the-vote campaigns ), and recently went on the popular podcast Call Her Daddy, which began life as a relationship and advice podcast and whose audience is now over two-thirds female and over 90% younger than 45.

Trumps campaign, meanwhile, has been... less deft. From Vance doubling down on demeaning childless women and suggesting they should have less voting power , to Trump promising to be womens protector, to, really, just all of the plain ol misogyny , its not surprising the gender gap isnt in Trumps favor .

You hear important people talking like this, and you say, What the hell? You know, People with children should have more votes than people without children. What? laughed Kamarck.

Between Vance and Trump, they are articulating an amazingly old-fashioned notion of womens role in society, she added.

The shift of young women leftward is not a particularly new trend. Women are regularly more liberal than their male peers , and young people are regularly more liberal than their older counterparts.

What is new, and intriguing, is the way that shift has picked up steam in recent years.

After [2015], it rises at a much faster clip, said Lydia Saad, director of U.S. social research at Gallup.

A Gallup analysis published by Saad and two co-authors in September found that the number of young women ages 18-29 who identify as liberal is increasing more rapidly than in the past. In the period from 2001 to 2007, some 28% of women in that age group identified as liberal, a share that increased to 32% in the period from 2008 to 2016. But in the period from 2016 to 2024, that number jumped even higher, to 40% of young women.

It definitely goes up at a faster rate when you get post-2015, with some significant ups and downs in there, Saad said. Its not a continuous upward trajectory.

She also noted that the research only focuses on women who were ages 18-29 at the time of polling, which means the data reflects the views of multiple generations, rather than the changing attitude of a steady cohort. The overall picture also shows some variance by race: White and Black women under age 50 have especially moved to the left, while Hispanic women have largely stayed the same or even shifted rightward.

But even with the ups and downs, weve ended up at a place thats significantly higher, on a percent level, than it was in 2015, Saad said.

And while young women are shifting left, young men are staying relatively moderate. Sixty-three percent of young women in 2001-2007 had views closer to those of liberals than of conservatives, a figure that jumped to 78% in the 2008-2016 period and then to 87% in the 2017-2024 period. Young men, meanwhile, saw those same figures move from 47% to 57%, and then fall to 50% for the period from 2017 to 2024.

The divide is becoming ever clearer as the 2024 election approaches. According to a fall 2024 Harvard Youth Poll, Harris has a 31-point lead over Trump among likely voters under 30 and when it comes to likely female voters in that age group, Harris leads 70% to 23%. Brat, indeed.