Alexandria Ocasio-Cortez has surprised many with an endorsement of Bernie Sanders.
This 2020 presidential bid is a big win for Sanders and could potentially hurt Elizabeth Warren.
Ocasio-Cortez is very popular among self-identified Democratic primary voters across the board.
About 55% of Sanders' supporters, and 63% of Warren supporters, have a favorable opinion of AOC.
The AOC endorsement is the single-most coveted endorsement of any Democrat who has not been a president before.
A quarter of Democrats then said that they'd value Ocasio-Cortez's endorsement in the primary.
This puts her just shy of the 27% who value the endorsement of former President Jimmy Carter.