The Bronx is brawling!

Rep. Alexandria Ocasio-Cortez hauled in an astonishing $1.43 million for her first re-election campaign, but will face multiple Republican challengers who are having no trouble raising their own cash, figures obtained by The Post show.

GOP donors have collectively given $1 million to the five candidates seeking the party’s nomination to challenge the Democratic superstar and self-described socialist in November 2020.

Bronx-born cop-turned-civics teacher John Cummings leads the pack of five declared Republican contenders in fundraising to defeat AOC with a total of $425,141 from 7,002 donors over the past quarter, his campaign told The Post.

“John Cummings’ very impressive fundraising totals in only 10 weeks is a testament to the strength of his candidacy and national detest for AOC,” said Bronx GOP Chair Mike Rendino.

Rendino, who kicked in $500 of his own funds to boost Cummings, added that “John’s message is resonating in the district because he’s one of us — a former NYPD officer and Bronx high school civics teacher taking on an out-of-touch socialist Twitter celebrity.”

Close on Cummings’ heels is Jamaican-born Queens resident Scherie Murray, who raised $424,000 from 8,106 contributors over the last quarter.

“The amount of support we’ve received since launching has been overwhelming,” Murray told The Post.

“Our movement is the only one capable of beating a radical leftist congresswoman that focuses on her Twitter account more than the people she was elected to represent,” Murray said.

Finally, entrepreneur Antoine Tucker brought in $20,000 from 472 people. The two other candidates — Bronx medical writer Ruth Papazian and Manhattan resident Miguel Hernandez — did not respond to messages asking for their totals.

Corbin Trent, a spokesman for AOC’s re-election campaign, said she raised $1.43 million since July, outpacing her first two quarters that brought in $700,000 and $1.2 million.

“The state, the district and progressives across the country continue to be supportive of Alexandria’s campaign to bring about real change while she fights for her district,” Trent said.

The eventual Republican challenger will have to climb a steep hill just to be competitive in the heavily Democratic 14th Congressional District, which includes swaths of western Queens and eastern portions of the Bronx.

There are 226,000 active registered Democratic voters there, compared to just 34,000 registered GOP voters, according to records kept by the state Board of Election.

All the fundraising figures were self-reported by individual campaigns ahead of next week’s required Federal Election Committee disclosures.