With more than 75 per cent of the vote counted in District 14, Ms Ocasio-Cortez – widely known simply by her initials as AOC – was on 69 per cent against 30 per cent for Republican challenger John Cummings.
Mr Cummings, a 60-year-old teacher and first-time Republican challenger, raised more than $10m in donations from across the country to make District 14 the second-most expensive House of Representatives contest in the nation.
After AP declared the result in her favour at 10.09pm local time, Ms Ocasio-Cortez thanked voters for backing her “despite the millions spent against us”.
“Serving NY-14 and fighting for working class families in Congress has been the greatest honor, privilege, & responsibility of my life,” she tweeted.
“Thank you to the Bronx & Queens for re-electing me to the House despite the millions spent against us, & trusting me to represent you once more.”
Ms Ocasio-Cortez, 31, has become a rising star in the party, earning her animosity from Republicans and repeated barbed comments from Donald Trump during his campaign rallies.
She herself raised more than $17m in donations for her 2020 race, however, galvanising support for her strong stance on climate change and a relatable style of politics, that saw her play video games on Twitch with voters during the campaign.
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