Democratic Socialist Alexandria Ocasio-Cortez also won a New York congressional district she wasn't running in

Alexandria Ocasio-Cortez, who rattled the world of Democratic politics last month when she beat 10-term incumbent Representative Joe Crowley in a New York congressional primary, also won a neighboring congressional district that she wasn't even running in.

Ocasio-Cortez won the Reform Party's primary for the 15th Congressional District with just nine write-in votes, according to the New York City Board of Elections as was first reported by New York Daily News.

The self-described Democratic Socialist took to Twitter to voice her surprise of the election results, which were certified by the city on Tuesday.

"Shockingly - and I'm told this is not a joke - we have ALSO won a primary in the neighboring 15th Congressional District via write-in campaign on the Reform line!" Ocasio-Cortez said. "While I am honored that so many Bronxites are excited about our campaign, I will remain the Dem nominee for NY-14."

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The 28-year-old Ocasio-Cortez had a low profile until she beat her Democratic incumbent rival in New York's 14th Congressional District. Crowley is the fourth-ranking Democrat in the House. He spent $3 million for his re-election bid compared with Ocasio-Cortez's $600,000. The shocking upset even surprised the young candidate.

Ocasio-Cortez is supported by the Democratic Socialists of America, a group that saw 35 times more membership sign-ups the day after her June 26 victory. She also campaigned on behalf of Vermont Senator Bernie Sanders in the 2016 presidential election, so it is no surprise she took up some of Sanders's far-left policy stances that seemed to do quite well with Democrats.

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Some of these include Medicare for all, free college education, increasing the minimum wage to $15 an hour and a new call to abolish Immigration Customs and Enforcement in the wake of thousands of children who are struggling to be reunited with their parents after being separated at the U.S.-Mexico border.

The young Democratic Socialist was Crowley's first primary opponent in 14 years. Crowley was considered to be a top future contender to fill House Minority Leader Nancy Pelosi's role as the highest-ranking Democrat in the House.

Come November, Ocasio-Cortez will face off against Republican Anthony Pappas, a St. John's University professor who teaches economics and finance.

Democratic Socialist Alexandria Ocasio-Cortez also won a New York congressional district she wasn't running in | U.S.