I don't think the native American thing is a big deal.
I grew up with kids who looked just as white as me but claimed to have some native American ancestry. It was a way to make yourself sound interesting. And I'm sure when Elizabeth Warren was young growing up in Oklahoma, it was an even more popular thing to talk about. Was it a dumb thing to talk about? sure. But every candidate has put out messages that make them seem silly and out of touch.
Especially Trump.

I would give any Democratic candidate a better than 50% chance of beating Trump, regardless of if they pick Biden or Warren. Now if they pick one of the fringe, one-note candidates like Tom steyer or Andrew Yang, they have no chance. But they're not going to pick one of those guys. They are going to pick somebody who is better known, and they will probably win.

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