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Sen. Elizabeth Warren (D-Mass.) is on good terms with some Democratic exes.

While she can't claim to have raised thousands of dollars from ex-boyfriends, like Sen. Amy Klobuchar (D-Minn.) can, Warren has remained quite friendly with several ex-Democratic presidential candidates. In an interview with NBC News, Warren said she's texted nature photos with Washington Gov. Jay Inslee (D) shortly after he dropped out of the race, talked math with Andrew Yang, and kept in touch with former Housing Secretary Julián Castro, who has endorsed her run.

But she says Sens. Kamala Harris (D-Calif.) and Kirsten Gillibrand (D-N.Y.) have particular insight into what NBC News calls the "loneliness" of the campaign trail, something Warren described as like "living in a movie that is running at high speed with everything coming so quickly."

"Kamala and Kirsten, in particular, ask me am I getting rest? Am I eating? And am I having some fun out there?" said Warren of her fellow women candidates. "It's a very personal experience to run. Running for president can be thrilling but also very lonely," she said. "The candidate stands alone."

Warren even got back in good graces with former Rep. John Delaney (D-Md.) after taking him down a few pegs in one of the first debates. Delaney said her call to wish him well after he dropped out was "quite lengthy and quite in-depth" and showed "she's not entirely self-absorbed. She actually listens."

Read more about Warren's relationship with her ex-competitors at NBC News.