“Women like me aren’t supposed to run for office,” she said in a campaign video that helped her defeat a 10-term, Democratic Party grandee in her first political race in a New York primary in June.

Overnight, Ocasio-Cortez went from total unknown to the toast of coastal America, profiled in Vogue, a guest on late-night chat shows and jetting around the country lending her rock-star status to other insurgent candidates.

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On Tuesday, she is virtually certain to be elected to Congress – an astonishing achievement for a woman who was working this year as a bartender – in a safe Democratic seat in diverse Queens and the Bronx.

Ocasio-Cortez once worked for the late senator Ted Kennedy while studying economics and international relations at Boston University. She has worked with female entrepreneurs in Africa and in education.

When she beat incumbent Joe Crowley, she was moonlighting as a bartender.

“It’s really one of the most remarkable stories I’ve ever heard,” said talk show host Jimmy Kimmel in a breathless introduction.

There’s no doubting her talent, crowd-appeal, idealism and passion for grass roots campaigning, riding what she hopes will be a blue wave in the midterms to ultimately overwhelm Donald Trump.

“It becomes way harder to hate up close, which is why the work of knocking on doors is so important,” she said to applause last month at an event organised by the LGBT community.

“I am like, ‘hey, we are fighting for universal care, for tuition-free public college, we are fighting for a living wage,’ and you see that kind of defence mechanism kind of come down.”

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But in America at large, such politics are pretty radical. She is a Democratic Socialist in the vein of failed 2016 presidential hopeful Bernie Sanders, on whose campaign she worked.

Ocasio-Cortez has compared the fight against climate change to the fight against Nazi Germany in the second world war, calling it a “major existential threat” and has likened electing Democrats to ending slavery.

The right has branded her politics “dangerous” and she has also taken hits from centrist stalwarts, former senator Joe Lieberman saying her primary win seemed “likely to hurt Congress, America and the Democratic Party”.

Only time will tell whether the progressive Democratic wing that she embodies represents the future or a Tea Party-style spin-off as mainstream liberals scramble for ways to contain Trump.

“On any given day, no one can agree if she is the next Sarah Palin, the next Obama or a Venezuelan dictator,” summed up Vogue.

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She has proved herself an engaging speaker on the campaign trail.

“She was very social media savvy, she worked very, very hard for every vote she had … and she is a really good candidate with good political instincts,” says Jeanne Zaino, a political scientist at Iona College.

“But we can’t forget the larger forces, there’s a real frustration … with the establishment,” she added. “I’m not sure she’d have won if her opponent wasn’t a leader of the Democratic Party.”

Pragmatists say she will eventually have to compromise her ideals. Debt-free college and universal health care sound appealing, but are expensive propositions.

Neither is it clear what kind of power she and other progressives will yield in the years ahead.

“A lot depends not just on what happens in 2018, because we will not see large numbers of progressives elected in office, but 2020-2022. These movements take a long time,” Zaino said.