Cummings acknowledged the disruptive nature of the new Congress; the freshman class will at times be at odds with other members of the Democratic caucus. Congresswoman Rashida Tlaib of Michigan launched a 24-hour news cycle when she declared she wanted to “impeach the motherfucker,” in reference to Trump. Tlaib and Ilhan Omar of Minnesota have also stoked controversy with their criticism of Israel—notably putting them at odds with some Democrats on the House Foreign Affairs Committee, on which Omar sits. Just last week, Ocasio-Cortez, Tlaib, Omar, and Congresswoman Ayanna Pressley, another freshman, signed a letter calling on the bipartisan conference committee negotiating a border security deal to cut, not increase, funding for the Department of Homeland Security and, specifically, the ICE and C.P.B. agencies—a move certain to complicate the negotiation effort.

But Cummings suggested that disagreement within the ranks is a considerable strength. “It is important that you have people like her—not only on my committee, but in the Congress—to remind folks of who we are, who we are as the Democratic Party, and who we have been for many years,” he explained. “And so, sure, when you do that like Ms. Cortez, you may ruffle a few feathers, but I think that, in the end, it will make us a better and stronger party.”

Last week, during a House Oversight Committee hearing on the cost of prescription drugs, the freshman congresswoman presented as measured and methodical as she probed the relationship between drug manufacturers and taxpayer-backed organizations like the National Institutes of Health. “She asked the best set of questions of anybody in her five minutes,” Cummings said, noting that the New York congresswoman stayed for the entire hearing, which stretched beyond the five-hour mark. “It was clear that she had done her homework.”

After years of Republican infighting on Capitol Hill, Trump allies have seized on this new, disruptive era in progressive politics as evidence that the Democratic Party, too, is in disarray. Right-wing media has eagerly latched on to these policy divisions, casting A.O.C. as the ringleader of a band of insurgents. Democrats I spoke with, however, argued that there have always been progressives and centrists under the party banner. Others pointed to the unified messaging around the shutdown as evidence that these tensions were overblown. “Maybe right-wing media is so sick of their Freedom Caucus thwarting everything they want to do that they finally want to create that sentiment here. I just don’t think it is going to happen,” the first congressional aide told me.

The freshman class is under no delusion that there is a one-size-fits-all approach to promoting progressive policy. “Every member of the freshman class has their own politics and their own experience,” an aide to a freshman lawmaker told me. But, they added, “there is tremendous kinship and excitement about this class. I honestly don’t give too much credence to the narrative around divisions.”

Underlying the various narratives surrounding A.O.C. and other members of the Democratic freshman class is a recognition of their power. Steve Doocy, Ainsley Earhardt, and Brian Kilmeade wouldn’t waste airtime attacking her, Tlaib, and Omar if they didn’t recognize that these women are threats to the ideology they seek to promote every morning. It is not unlike how the Republican Party has spent billions of dollars disparaging Pelosi, whose skills as a master legislator were on full display during the shutdown. (Two sources suggested to me that Pelosi likely sees herself in Ocasio-Cortez.)

A.O.C. and her fellow progressives have already had an indelible impact on the national political discourse, despite only being in office a few weeks. Since Ocasio-Cortez floated a 70 percent marginal tax rate on income over $10 million during a 60 Minutes interview, the proposal has emerged as a talking point for potential 2020 hopefuls. According to one recent poll, 59 percent of registered American voters support the plan—including 45 percent of Republicans. Similarly, while A.O.C.’s bold yet publicly undefined Green New Deal initially drew criticism and caused some turmoil within the Democratic Party, it has quickly emerged as something of a progressive litmus test for the Democratic field. “She is a Democrat and she is a strong, vocal advocate for our agenda,” the third congressional aide told me. “I think while initially fearful—and maybe even right to be fearful because of some of the early things that were going on—she has now come into her own and realized that she has a lot of power.”

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