According to the NV State Dems, 2,113 Bernie delegates and 963 alternates were elected at county conventions to attend the NV state convention, versus 1,712 Hillary delegates and 854 alternates. Some sources show the number of delegates for both campaigns 10 or 11 higher, but not 500 off.
All they had to do was show up and Sanders would have had a clear majority and won 7 of the 12 national delegates available, 4 of the 7 At-Large delegates and 3 of the 5 Pledged Elected Officials, since the rules established in September 2015 show that the state convention attendees elect them.
Instead, 1,683 out of 2,566 Hillary delegates or alternates (63.5%) showed up to fill their 1,712 seats, but only 1,670 out of 3,076 Bernie delegates or alternates (54.3%) showed up to fill their 2,113 seats. Clearly this would be understandably disappointing for those Bernie delegates, to lose by just a few.
Eight Bernie delegates who tried to register were disqualified by the credentials committee and then twelve uncommitted delegates decided to support Hillary resulting in a final count of 1,695 to 1,662. That gave Hillary the majority at the convention, so she won 7 of the 12 available national delegates.
Nothing the credentials committee or rules committee decided impacted that delegate allocation. The only factor that determined the outcome was that 500 more Bernie supporters than Hillary supporters failed to show up, allowing Clinton to more than overcome her 400 delegate deficit.
Brad Schrager, the attorney for the Nevada State Democratic Party, described what happened next:
Surprised and outraged at the idea of being out-organized and thus outnumbered in the convention hall by Clinton delegates, a portion of the Sanders delegation rushed the dais immediately upon the opening of the convention and halted the progress of any convention business for much of the day.
...The Sanders Campaign spent its time either ignoring or profiting from the chaos it did much to create and nothing to diminish or mitigate. It was clear to the NSDP that part of the approach by the Sanders Campaign was to employ these easily-incensed delegates as shock troops to sway the convention proceedings. At the very least, these delegates became a way for the Sanders Campaign to seek the advantage of disruption at any particular moment while trying to disavow any responsibility for their actions even as it was ongoing. At no time did any Sanders representative make anything more than token gestures towards peace in the hall, and at the times of most intense crisis offered little more than shrugs and smirks.
The most egregious instance of the Sanders Campaign inciting disruption—and yes, violence—came as the State Convention’s Credentials Committee completed its work. Adam Gillette, part of National Delegate Operations Team for the official Sanders Campaign, drafted and arranged for a member of that committee to attempt to deliver an incendiary, inaccurate, and wholly unauthorized “minority report” charging that the Credentials Committee had fraudulently denied 64 Sanders delegates their eligibility. The final delegate count had provided the Clinton Campaign with a 33 delegate advantage in the hall; one can imagine the rage occasioned by this inflammatory charge, tossed into the tinderbox of a tense convention hall. Not only did this discredit the work of the Credentials Committee—which featured five Sanders delegates and five Clinton delegates and a Sanders co-chair, and who worked all day under extremely trying conditions to be fair and diligent in their duties—it called into question the entirety of the proceedings because it indicated to an irrational minority that the proceedings had been rigged against them. Forcing their way onto the dais to deliver this paranoid fantasy of fraud and delegate theft was clearly intended to throw the proceedings into disarray. It succeeded. From that moment on, there was little hope for any peace or mutual understanding and respect between Sanders delegates and the NSDP; the mantra became simply that the convention had been stolen from the Sanders Campaign.
Never mind that six of the 64 potential Sanders delegates referenced had been seated after investigation, or that most of the remaining 58 potential delegates had been disqualified—appropriately, and by a panel evenly split between the campaigns—for not being registered Democratic voters in Nevada. Never mind that the same Credentials Committee had disqualified Clinton delegates for various reasons as well. Never mind, further, that just eight of those 64 potential Sanders delegates even attempted to register for the State Convention. All that mattered was the creation of a narrative of fraud and dispossession, which the Sanders Campaign fomented intentionally for its own political gain. This was an unconscionable act by an official Sanders Campaign representative, with full knowledge of its likely impact on the convention.
UPDATE: Still no comment from Bernie himself:
Here is a link to the video described in this tweet.
Meanwhile Sanders campaign staffer basically confirms what happened:
Let me explain what happened today. We were at 110% registration for delegates for the convention, they just didn't show up and check in, and a lot of our delegates had credentialing issues.
NV State Party has restated only eight Sanders delegates were prevented from registering.