Nate Silver's take on Ocasio-Cortez's victory.

Looks like soon we’re wrapping up for the evening, so I’d like to reiterate one last time the not-so-hot take that primaries are extremely idiosyncratic and one ought to be cautious about global conclusions from local events. On the one hand, Ocasio-Cortez’s win was extremely impressive in New York 14 tonight against the establishment Democrat Joe Crowley; on the other hand, Chelsea Manning received only 6 percent of the vote in her challenge to establishment Democrat Ben Cardin in Maryland’s U.S. Senate primary. (Cardin won with 81 percent.)

I think pundits might do better to focus on the particular combination of attributes that Ocasio-Cortez brought to the table: young, Latina, from the community, media-savvy enough to draw a lot of coverage from lefty outlets (but not very much from mainstream outlets, which she may not have wanted anyway), ran some good ads, very openly and proudly a progressive Democratic socialist, but also running against an old white dude who, while mostly a party-line Democrat, was asleep at the wheel in a district that had undergone a lot of demographic change. And the race was maybe in an in-between zone whereas it was just competitive enough that her voters were excited and turned out, but also enough to the periphery of the radar enough that Crowley’s voters didn’t.

Which of those elements were most essential to her success? Which of those factors might be replicated elsewhere? It’s hard to say. My personal bias is to think being cut from the cloth of the district is pretty important, whereas candidates who are famous for other reasons, such as Cynthia Nixon (who hasn’t made up her deficit with Andrew Cuomo in the polls) aren’t going to resonate in the same way and won’t have the same underdog quality. But maybe the combination is pretty unique — and will be hard to replicate — given that she’s the first challenger to defeat a Democratic incumbent for the U.S. House since 2014.