(CNN) At first glance, the upset victory scored by Alexandria Ocasio-Cortez over 10-term Rep. Joe Crowley in New York's 14th District Democratic primary is no big deal for Democrats' chances of flipping the House in November. After all, the Bronx and Queens seat is overwhelmingly Democratic and has zero effect on Democrats' fight for the majority.

But that first glance is very, very deceiving. This isn't just about a single House race. This is about the struggle for the future of the Democratic Party -- both in New York and nationally. This is about the kind of candidate Democratic voters want. This is about the kind of leaders the Democratic Party will have after 2018.

In short: Ocasio-Cortez's victory is about a whole hell of a lot more than just a single strongly Democratic House seat. Below, four major lessons Democrats should take from her win -- the primary upset of the 2018 cycle to date.

1. The Democratic base is sick of the establishment

Donald Trump's hostile takeover of the Republican Party in 2016 -- and the establishment's acquiescence to him in 2017 and 2018 -- put a massive spotlight on the divide between the GOP party leadership and the Republican base.

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