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Less than a year ago, 28-year-old Alexandria Ocasio-Cortez was bartending and waiting tables in Manhattan to support her family. On Tuesday night, she unseated a potential speaker of the House, and is on her way to becoming the youngest woman in Congress.

“We meet a machine with a movement,” Ocasio-Cortez told a TV reporter as returns from the primary election rolled in. “That is what we have done today.”

Ocasio-Cortez, a Bronx-born member of the Democratic Socialists of America, beat 10-term incumbent Democrat Joe Crowley by a 15-point margin in New York’s 14th congressional district, which contains parts of Queens and the Bronx. It was the most surprising in a slew of progressive wins against more establishment candidates on Tuesday. Crowley hadn’t had a challenge from a member of his own party since 2004, and his loss drew comparisons to that of House Republican Majority Leader Eric Cantor in 2014, when he was defeated by tea-party candidate Dave Brat.

In this race, Ocasio-Cortez was the insurgent candidate, taking on an already liberal Crowley from the left, and speaking loudly and enthusiastically against President Trump. “It used to be that a Democratic primary was about who the better Democrat was,” said one Democratic strategist who spoke on the condition of anonymity to talk candidly about the race. “Now it’s about who is the better progressive. … [Democratic] voters want their reps out in front of [Immigration and Customs Enforcement], attacking Trump, and being loud for what they believe.”

Crowley is one of the most powerful Democrats in the House. He’s been chair of the House Democratic Caucus since 2017, and was widely viewed as a possible speaker-in-waiting. He was backed by Wall Street and dozens of labor unions, and raised more than $3 million during the primary, including donations from corporations like Facebook and Google. Ocasio-Cortez, who has never held elected office, raised roughly $300,000, and won the endorsement of progressive groups like Our Revolution, Move On, and the Black Lives Caucus.

Crowley has liberal bona fides: He’s been a strong proponent of the Affordable Care Act and, more recently, Medicare-for-all legislation, and is a harsh critic of Trump. But Ocasio-Cortez fashioned herself as the more progressive choice—a champion for workers and for racial justice. A former Bernie Sanders organizer, the Democrat campaigned on a federal jobs guarantee, cracking down on Wall Street, and tuition-free public education, and she eschewed corporate political-action committee donations. She was an early proponent of abolishing ICE, a position that amassed support this past week amid controversy over the Trump administration’s family-separation policy. On Tuesday, Ocasio-Cortez’s campaign posted a video of the candidate berating a Border Patrol officer at a facility housing immigrant children.

But it was a May 30 campaign ad that brought Ocasio-Cortez’s candidacy to the attention of Americans nationwide: “Women like me aren’t supposed to run for office,” she says at the beginning of the ad, which knocks Crowley for, among other things, living outside his district and sending his children to schools in Virginia.

Crowley, a 56-year-old white man, also doesn’t look like a lot of his constituents: Half of the 14th district’s residents are immigrants, and 70 percent are people of color. Ocasio-Cortez grew up with two working-class parents in the Bronx. Her mother was born in Puerto Rico, and her father was from the South Bronx. The strategist told me the race illustrated not only a growing energy on the left, but also the importance of representatives being in tune with their district. “Being out of touch is never a good look,” the strategist said. “It brought down Cantor for the Republicans, and it claims a similarly situated Dem here.”

It’s important to note, though, that the dynamics at play in the 14th district were unique. New York is the only state with a split primary system, with its federal and state elections held three months apart. Turnout is always low for these primaries, especially in midterm years: On Tuesday, fewer than 28,000 votes were cast in the 14th district, which has more than 710,000 residents and 292,000 active voters. Of those, Ocasio-Cortez won nearly 16,000 to Crowley’s 11,800.

And it’s possible that many voters loyal to Crowley didn’t realize he was in trouble, and therefore didn’t turn out to vote. “It’s like a rogue wave: You don’t see it forming and by the time it hits you, it’s too late. That’s what this was,” said former New York Representative Steve Israel, who once served as the chair of the Democratic Congressional Campaign Committee and whose district also contained parts of Queens. However, Israel doesn’t believe the election portends bad news for Democratic incumbents nationwide. “If you’re an incumbent in an upcoming primary, what happened in Queens is going to raise your antenna,” he said. “But I do not think this sends a national signal.”

Even so, the young Democrat’s win does mirror one prevailing theme of this year’s primaries: Women are running—and winning—in Democratic primaries at a record-high rate. “The drive to elect women is defining 2018’s Democratic primaries,” wrote Cook Political Report’s Dave Wasserman in May. And a number of those first-time women candidates are challenging establishment incumbents from the left, relying on grassroots support to do so. “If you are an old white guy in a Democratic district with a woman running to your left, it might be a good time to update the resume,” said the strategist, “because women, young and old, minority or not, are turning out in huge numbers, and in poll after poll they are saying that they are fed up.”

A number of other progressives won their primaries on Tuesday night, including former NAACP chair Ben Jealous, who won the Democratic gubernatorial primary in Maryland. Tedra Cobb won in New York’s 21st district with the support of Indivisible, a grassroots group whose mission is “to resist the Trump Agenda.” In New York’s 24th, progressive candidate Dana Balter defeated Juanita Perez Williams, who had the backing of the national party.

“There is a profound discontent with status-quo rhetoric and incrementalism,” said Charlie King, a New York-based political consultant. “Rightly or wrongly, that’s what Trump has brought to the table. If you’re not prepared to fight in this new Trump era that way, you’re gonna be overrun.”

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