Massachusetts Sen. Elizabeth Warren will be the only female Democratic Senator to not endorse Hillary Clinton.

Monday on MSNBC’s “Andrea Mitchell Reports,” Mitchell and Washington Post correspondent Anne Gearan discussed Warren’s snub with Mitchell, suggesting, “This is something the campaign doesn’t want to talk about, that they have got 13 of 14 but Elizabeth Warren is the outlier.”

Of the 14 Democratic Senators, 13 will endorse Clinton for president, all except Warren who has yet to endorse anyone.

Gearan said the Clinton campaign’s announcement of the planned endorsement “didn’t mention that the universe is 14” Democratic senators. Instead, the statement said that 13 Senators would be endorsing Clinton.

Mitchell added, “Now, I don’t think that Warren has officially endorsed Bernie Sanders, her friend and colleague.”

Gearan responded, “She has not. She’s not endorsed anyone, nor has she given a timeline for when she might or said with great precision what she’s going to base that decision on.”

“Clearly, she’s holding out for leverage here,” explained Gearan. “Whomever she ends up endorsing would then you know, then sort of owe some allegiance on the issues that Senator Warren cares most about, progressive economic issues primarily.”

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