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).

“I’m 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.

“It’s popping out in the polling because it’s 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.

Trump’s 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 women’s “protector,” to, really, just all of the plain ol’ misogyny, it’s not surprising the gender gap isn’t in Trump’s 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 women’s 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. “It’s 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, we’ve ended up at a place that’s 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.

Combine that with women’s greater propensity to actually show up to the polls, and things get even hotter. In terms of ballot box turnout, women have outshone men in every presidential election since 1980. In 2020, 68% of eligible women showed up to vote, compared to 65% of men. In a presidential race that is already uncomfortably close, that 3% difference could be crucial.

EMILY’s List, which has been tracking women’s interest in voting, says the organization saw a 56-point increase between April and late July in the share of women under 45 who said they felt motivated to vote. (Late July is, perhaps not coincidentally, when President Joe Biden dropped out of the race and threw his support behind Harris.)

“Youth turnout has been historic over the past three election cycles,” said Abby Kiesa, deputy director at Tufts University’s Center for Information & Research on Civic Learning and Engagement, which studies youth political engagement. “The last presidential election, we saw young women turn out at rates higher than their peers who identify as men in every race and ethnicity for which we had data.” In 2020, 50% of young voters cast their ballots — which, while still lower than the 67% national turnout, was an 11% increase over 2016.

In 2024, CIRCLE estimates that Gen Z comprises some 41 million eligible voters, of which half are women, and that young women have swung for the Democratic candidate by an average of 2 to 1 in every election since 2008. In 2024, the youth voting influence is expected to be strongest in states that are already battlegrounds — Michigan, Wisconsin and Pennsylvania top the list.

To boot, many of these battleground states already have a substantial gender gap when it comes to turnout. An analysis published by Kamarck in early October, which combined 2020 voter turnout by gender with 2024 candidate preference by gender, found that the gender gap favors Harris in five out of seven swing states. Only in Georgia and Arizona does the gender discrepancy favor Trump.

“If the composition of the electorate between men and women remains the same as it was in 2020, Harris could win Pennsylvania, Michigan, Wisconsin, and Nevada ― all states Biden won in 2020,” plus North Carolina, Kamarck wrote.

Saad’s analysis cited a few issues as key to the shift among young women, such as climate, abortion and gun violence ― all issues where Harris has a substantial lead over Trump with young voters.

Kamarck highlighted abortion in particular. “You can’t dismiss abortion,” she said. “It is the issue that has gotten women of all ages, but particularly young women, interested in politics and realizing that they have a stake in politics. I think that’s the first lesson, is if you have a stake in something in politics, then you get interested in elections.” EMILY’s List also notes that abortion has been a driving issue in motivating young women voters.

Kiesa, though, cautioned that what CIRCLE has seen in its surveys is less concrete.

“Across the board, with one exception, the cost of living and inflation was the number one issue” for young voters, regardless of race or gender, she said. “The only exception to that was Black men, who said jobs that pay a living wage.”

“People did not rank, even young women did not rank, expanding access to abortion reproductive care in their top three,” she noted.

Young women, though, are more likely than young men to be involved in liberal-leaning social movements like Black Lives Matter, #MeToo, environmental activism and gun violence prevention. Particularly involved are young women of color, who Kiesa notes have taken on “significant” leadership in activism work.

“Younger Americans are simply more accepting of diversity, whether it’s racial, whether it’s gay and lesbian and queer, or whatever,” Kamarck said.

Annie Wu Henry is a political and digital strategist who has worked with multiple Democratic campaigns. She also works on a volunteer basis as the campaign manager for Swifties4Kamala, a coalition of Swift fans pushing to get Harris elected president. At 28, she is right smack in the “youth” age group herself. She says the issues people bring to the coalition are diverse.

“There are many folks who are large advocates for things like abortion access, and reproductive freedoms and rights. There are many folks that are passionate about things like climate change or gun control,” Henry said. “There are many folks who are passionate about affordable housing and disability access. We have Swifties who are passionate about things across the [gamut], or multiple things at once.”

She notes that Swifties4Kamala, which has some 3,700 volunteers and says it has raised $150,000 for the Harris campaign, is not a monolith in any respect, despite the fact that Swift’s fan base is heavily perceived as young and female. (In fact, one of the co-founders is a trans man.)

“It’s becoming more and more apparent that everything is political, and for so many folks, for women, for queer people, for people of color, for people whose identities span multiple of those things, I think our existence is political,” said Henry. And people are involved: She says that as of late October, the movement has made more than 370,000 phone calls and sent 5.5 million texts to advocate for Harris. “I think we’re seeing the politicization of our bodies, the politicization of what we should or should not be doing in society, the different discourse of ‘childless cat women’ and how that’s unacceptable.”

Kamarck thinks the shift is just as much about Republicans turning young female voters off as it is about Democrats appealing to them.

“It used to be that one of the reasons suburban women voted Republican ― or women in corporate America voted Republican ― [was] when we fought elections on things like taxation, things like freedom from too much regulation, et cetera,” she said.

“Suddenly we’re not talking about those things anymore,” she said. “We’re talking about ‘Women should have a lot of babies,’ and ‘If they’re pregnant, they should be forced to have a child that they don’t want,’ et cetera. Suddenly it’s a different conversation.”

Saad notes that it’s impossible to point to direct causes and effects, or to zero in on one thing or another as the One True Reason. But she adds that 2015 seems to be a clear pivot point, citing a few big things that happened around that time.

“Perhaps the Obergefell decision, or the prominence around gay marriage and gay rights at a time when so many more young women are coming out as LGBT, could be a factor,” Saad said. Or there’s the fact that women who are ages 18 to 29 now were largely children and teens nine years ago, and have grown up in a different political climate.

“Perhaps the start of the 2016 election — you have Hillary Clinton running, so now you have a very prominent female leader at the same time you have Trump, and however they would have reacted to him early on in that process,” she said. “Those are all very reasonable events to point to on the timeline as things that could have been formative.”

Kamarck also nodded to the idea of women’s visibility on the political stage.

“Suddenly you have a female candidate who’s close to the presidency, and the second one in the lifetime of most young women. Although they might have been kids when Hillary ran,” she said. “I think that in the way that Obama’s presidency sort of crystallized a lot of racism that was under the surface, I think this is crystallizing a lot of feelings about the role of women in society, and bringing a lot of those up.”

“Young women were raised in a society where they were continually taught they could do anything,” she added. “And then to have a certain part of the political world saying, ‘Oh, no, we really think it’s important that you stay home and have children.’ It’s kind of a slap in the face.”