Supporters of Democratic presidential candidate Bernie Sanders (I-VT) left a mock caucus at Iowa’s Drake University in protest after Democratic presidential candidate Elizabeth Warren (D-MA) won and Sanders failed to meet the event’s “viability threshold.”

With voting in Iowa’s statewide caucuses just a week away, colleges held simulations of the events across the state Monday night. NBC News campaign embed Ben Pu covered the Drake University mock caucus, and reported that after the first round, only Warren and former South Bend, Indiana Mayor Pete Buttigieg exceeded the 15 percent viability threshold.

“!!! Only Buttigieg and Warren are viable. Supporters are being peeled away from the other groups,” Pu wrote.

!!! Only Buttigieg and Warren are viable. Supporters are being peeled away from the other groups. https://t.co/RfDpvmRNq7 — Ben Pu (@BenPu_nbc) January 28, 2020

NBC News’ Maura Barrett, one of apparently a zillion or so reporters at this event, reported that Sanders got 21 votes in the first round, and was dwarfed by Warren at 73 and Mayor Pete at 47.

The numbers from the first alignment: Bennet 0

Biden 8

Bloomberg 8

Buttigieg 47

Delaney 1

Gabbard 1

Klobuchar 11

Patrick 0

Sanders 21

Steyer 7

Warren 73

Yang 16 — Maura Barrett (@MauraBarrettNBC) January 28, 2020

CBS News’ Ed O’Keefe also covered the event, and reported that the second-choice deliberations were “intense.”

Watching those forced to make a second choice is intense. Buttigieg and Warren team leaders are seeking out the undecideds. @adam_brew heard one now-displaced @amyklobuchar supporter say: “I hate this.” — Ed O’Keefe (@edokeefe) January 28, 2020

Pu reported, “Warren supporters attempt to convince Sanders supporters. Almost none have budged,” and explained “As an unviable group – if they don’t realign, they’re effectively going home.”

Warren supporters attempt to convince Sanders supporters. Almost none have budged. As an unviable group – if they don’t realign, they’re effectively going home. pic.twitter.com/A2Wwd25qwt — Ben Pu (@BenPu_nbc) January 28, 2020

Pu reported that the Sanders group failed at gaining additional supporters on the second round, and rather than realign with another candidate, they went home.

“In a possible sign of things to come, the Sanders corner, despite previously being labeled unviable, has not budged,” Pu wrote. “Three Yang supporters realigned to ‘Tom Steyer’s daughter’ (she advocated for Steyer tonight). Now in protest, the Sanders people are just straight up going home.”

In a possible sign of things to come, the Sanders corner, despite previously being labeled unviable, has not budged. Three Yang supporters realigned to “Tom Steyer’s daughter” (she advocated for Steyer tonight). Now in protest, the Sanders people are just straight up going home. — Ben Pu (@BenPu_nbc) January 28, 2020

In the end, most of the participants lined up between one of the two viable candidates.

.@ewarren ultimately had 87 students in her “corner” while @PeteButtigieg had 66. So, Warren got 5 “delegates” and Buttigieg received 4. — Maura Barrett (@MauraBarrettNBC) January 28, 2020

As Barrett reported, Warren got 87 students into her corner, while Buttigieg managed 66.

Sanders is polling well enough in Iowa that he’s unlikely to miss the viability threshold in the actual caucus, so Pu was likely referring to the prospect of a Sanders loss in the overall primary delegate race.

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