THE LEDE

The last debate: The Democrats staged their last official confrontation not over the big divisions between left and center but with the left-wing candidates who really need one another’s voters to switch sides fighting for their wing of the party. In the great primary tradition, usually the candidate who stays out of that fight — in this case Biden — wins. But we’ve also got a long way to go, and room for some other self-immolating face-off.

How'd that guy get onstage? People don't talk much about how Tom Steyer got so rich. But it’s helpful to understand how he took an arbitrageur’s approach to a market the Democratic National Committee thought couldn't be gamed.

READ RECEIPTS

Julián Castro

I texted again this week with Julián Castro, the former San Antonio mayor and Obama cabinet member who dropped out of the race in early January, about his endorsement of Elizabeth Warren, that moment with Bernie, his views on the media, and his brother’s questionable social media choices.

BEN SMITH: Secretary - nice seeing you in Des Moines, and thanks for doing this again. To begin with, can you send over a selfie and tell me what you're to? (Up to right now that is.) IMAGE DESCRIPTION: Selfie of Julian Castro

JULIAN CASTRO: Hey, Ben- good to hear from you. Didn't think I'd be back in Des Moines so soon, but not I'm back in San Antonio with my family at home. BEN SMITH: To begin with: You ended your own campaign in January. Was there a particular moment it became clear to you that you had to pull out? JULIAN CASTRO: Despite not making recent debates, we kept fighting hoping to see something change in the polling. It became clear over the holidays that it just wasn't our time.

BEN SMITH: What did you feel in that moment? Relief? Frustration? JULIAN CASTRO: Of course it's a disappointment. To your supporters, to your staff, and to yourself. But I am proud of what we accomplished, what we stood up for. We made a positive impact on this race. We spoke up for those who aren't often spoken up for; put out good ideas that have shaped the policy debate. So more than anything, I feel proud. BEN SMITH: And did you immediately get a hard sell from ... 10 other candidates for your endorsement?

JULIAN CASTRO: Haha I got a few calls, but they were mostly just well wishes. BEN SMITH: You moved pretty quickly to support Warren. Why? JULIAN CASTRO: It wasn't hard for me to endorse Senator Warren. We share a similar vision for the future of our country- one where everyone has a chance to reach their dreams the way we've both been blessed to reach ours. She's got the right experience, a winning track record, and can unite our party and nation to beat Trump. I'm proud to support her.

IMAGE DESCRIPTION: Twwet from @GaryGrumbach reading, ''Sen. @BernieSanders gave his first response to what him and Sen. Elizabeth Warren discussed after the debate last night. 'About the weather,' Sanders said in response to my question.'' BEN SMITH: So do you think you could shed any light on this?

JULIAN CASTRO: Bernie and Elizabeth have been friends and colleagues for a long time. I'll leave it to them to comment on their private discussions. But what I'll say is what I've said before: I believe Elizabeth- and I know damn well she can win, as she's done throughout her career. BEN SMITH: When you're on message, sir, you're on message. Are you at all worried that this is going the way of 2016 -- with deeply alienated Sanders supporters and a divided party? This was a headline today ...

IMAGE DESCRIPTION: Headline reading, ''Bernie Sanders' Very Online Fans are Filling Elizabeth Warren's Mentions With Snakes.'' Snake emoji. JULIAN CASTRO: OF course we want to avoid the factionalism and division we saw coming out of the 2016 primary. But I think too often journalists look o Twitter or the dark corners of the internet to take their queues about the things voters care about.

These attacks on her and her supporters are sexist and counterproductive, but they're unrepresentative of the views of a vast majority of Bernie's supporters. I have a great deal of respect for Bernie and know the vast majority of his supporters want the same things we all want: a strong positive vision for our country's future and a candidate who can beat Trump. That's why I think it's important to nominate someone like Elizabeth who can bring alll parts of our party together and excite them to turn out to defeat Trump.

BEN SMITH: There's a lot of anger right now among Democrats at the media for promoting this conflict. Do you think it's the media's fault? JULIAN CASTRO: The media have embraced certain values, such as conflict, that turn what should be, all things considered, minor stories into major blowups according to the press. It's classic sensationalism amidst the backdrop of horserace coverage.

IMAGE DESCRIPTION: Tweet from @JoaquinCastroTX reading. ''I've been asked whether I plan to shave my beard- the beard stays (for now)!'' with a selfie of unsmiling Joaquin Castro in a white tshirt in the dark. BAN SMITH: And finally, I wondered if your could clear up one other confusing situation: What is happening here?? JULIAN CASTRO: Your guess is as good as mine!

BEN SMITH: Haha. Thanks for doing this! JULIAN CASTRO: Happy to do it. I'll catch you in Iowa soon, I'm sure. BEN SMITH: See you there!

ON THE TRAIL WITH BUZZFEED NEWS

Speaking of conflicts, the one between Elizabeth Warren and Bernie Sanders is not exactly over, Molly, Ruby, and Nidhi report from the debate.

And from Nidhi in Nevada: Immigration politics continue to be really complicated for Joe Biden.

Black Lives Matter activists won’t leave Pete Buttigieg alone, Molly and Henry report from Iowa.

On Capitol Hill, Addy caught up with Alexandria Ocasio-Cortez, who said she thought it’s “important to say a woman can win” and believes that Sanders thinks so too.

📝 This letter was edited and brought to you by Ben Smith, Veronica Dulin, and BuzzFeed News. You can always reach us here.

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