This early in the Democratic Presidential campaign, no one yet knows what the mood of the 2020 political season will be—whether it will reflect the angry, reactionary energy that put Trump in the White House, in 2016, or the progressive opposition that gave Democrats control of the House, in 2018. In the vast, still expanding field of Democratic contenders (“All my friends are running for President,” Senator Brian Schatz, of Hawaii, said earlier this year), no one has associated herself so exactly with the spirit of 2018 as Kirsten Gillibrand, the fifty-two-year-old junior senator from New York. Gillibrand is short, trim, and blond, with an intent manner. She is often photographed staring straight ahead, and when we met for lunch on Fifty-seventh Street, on Monday, I swear she maintained eye contact for forty-five minutes straight. She spoke in full paragraphs and listened carefully, interrupting only twice, when she found a question a little annoying, both times interjecting murmured praise for the soup.

Gillibrand settled quickly into her natural mode, at once effusive and polished. She reeled off statistics to prove that “systemic bias” made the indignities of American life sharpest for women of color—who are disproportionately likely to die in childbirth or before their children turn one, and who are doubly damned on student debt because they tend to have fewer resources to pay for college and then face a severe pay gap—and to outline her legislative remedies. “I’ve got a lot of new ideas,” she said assuredly. Gillibrand was a Kappa Kappa Gamma at Dartmouth, where she was also a varsity squash player; as a corporate attorney, she worked on a team that defended the tobacco giant Phillip Morris; she recently posted videos of her early morning workouts on Instagram. In 2017, as the women’s movement was consolidating, it was easy for activists to be cynical about the presence of wealthy, professional white women. Here come the Kappas. But what if the Kappas had radicalized? In December, Gillibrand tweeted:

Our future is:

Female

Intersectional

Powered by belief in one another.

It was easy to see this as at least a little bit of a performance. The language of intersectionality has not, until recently, been Gillibrand’s. Senator Marco Rubio and Donald Trump, Jr., tweeted mocking replies. The obvious assumption was that Gillibrand was being opportunistic. The more interesting possibility was that she had changed.

The terms in which Gillibrand describes her evolution are moral, not political. She did not always see the experience of others clearly, she says, but now she does. She first entered politics riding the Democratic wave in 2006, when she won a reddish House district from a Republican incumbent in upstate New York. Gillibrand ran in favor of withdrawing troops from Iraq and for dramatic expansions of health-care coverage, but during her campaign, and while in office, she also took some more conservative positions. She earned an A rating from the National Rifle Association for her voting record on gun rights, and opposed state efforts to issue driver’s licenses to undocumented immigrants. In 2009, Governor David Paterson appointed Gillibrand to fill Hillary Clinton’s former U.S. Senate seat; once she acquired a more progressive constituency, those earlier positions began to evaporate. Gillibrand now attributes her turn on gun violence (most recently, the N.R.A. gave her an F) to meeting the mother of a Brooklyn teen-ager who was killed by a stray bullet. In midlife, a moral turn. She described the experience to the CBS reporter Sharyn Alfonsi, on “60 Minutes,” last year:

Gillibrand: “You immediately experience the feeling that I couldn’t have been more wrong—you know, I only had the lens of upstate New York.” Alfonsi: “But you had lived in New York City—” Gillibrand: “I know.” Alfonsi: “—for a decade.” Gillibrand (evenly, and right away): “And that’s why I was embarrassed.”

Politicians understand that positioning is contingent, and most—caught between an old position and a new one—will say so, or at least imply it. When I asked Gillibrand if she thought that her pro-gun and anti-immigration positions were simply what it took for a Democrat to get elected in a district like hers in the late Bush era, Gillibrand said, essentially, no. “I don’t believe that I needed to take those positions and I regret that I did—I think it was just my own failing.” She went on, “I shouldn’t have, just from a moral perspective.”

Lately Gillibrand has been talking often about greed as a controlling force in society. She made the same criticisms of the tax breaks given to Amazon in exchange for a New York headquarters as other progressives, but when we spoke she made a point of denouncing what she described as the immorality of the deal. Gillibrand said, “I’ve realized over the past twelve years”—the time she’s been in Congress—“that the biggest impediment we have in Washington are these circles and systems of power that have been in place for a very long time that will not let go their grip, and that power is based on corruption and greed. So anytime there is something that you know—as a mother of young kids, as a legislator—needs to get done, and it’s not getting done, I will find you the reason and its almost all based on greed.” She went on, “I believe I have the courage and the tenacity and the fearless determination to take on that level of corruption and greed, because I can see it. And I know that everything I want to achieve for the people I represent, there’s something standing in my way.”

To listen to Gillibrand sometimes is to hear the crusading tone of the last century’s progressive movement translated into the more modern political form of talking points. Gillibrand’s maternal grandmother was one of the most powerful club politicians in upstate New York (her father was an Albany lawyer and lobbyist), and her mother was one of three women in her law-school class. The tradition was of accomplished women. “My generation was among the first that was told by our parents as young women, there’s nothing you can’t do,” she said. “For a lot of us, we got out in the workplace and saw systemic bias and gender discrimination, and we were almost—at least for myself—shocked that it existed, because we thought our mothers and grandmothers had taken it out for us. So there was a real awakening, at least for a lot of my friends in the last ten years, twenty years, as they climbed the ladder.” She recalled that, when she was a fifth-year associate at the white-shoe law firm Davis Polk, six associates were up for partner: the three men made it, and the three women did not. “I think for all of us it happened at different stages in our lives and careers,” Gillibrand said. “I just began to see this—it’s not as easy as you think it might be.”