If Nevada's state Democratic convention is any indication of what "party unity" will look like at July's national convention in Philadelphia, Hillary Clinton should be worried.
As veteran Nevada political writer Jon Ralston reports, an argument over convention rules and procedures on Saturday descended into chaos.
"Dozens of Sanders delegates exploded in anger at what they called an anti-democratic attempt to steal the convention from them," he recounts.
In the Byzantine world of Nevada presidential caucus politics, Mrs Clinton had won more votes - and state delegates - than Mr Sanders in the first round on 20 February. That was the "Nevada caucus" that got all the attention, with candidates holding rallies in Las Vegas and wall-to-wall media coverage.
It marked an inflection point in the Democratic presidential race, as Mrs Clinton shook off a crushing defeat in New Hampshire and went on to dominate the southern states that followed, building a lead she will almost certainly carry to the national convention.
In Nevada, however, that first day of voting was only the beginning. In an intermediary round of county caucuses, the Sanders campaign turned out greater numbers, which tilted the balance toward his side. At the state convention on Saturday, Mrs Clinton once again had the higher turnout - in part because some Sanders delegates showed up late, provided insufficient information or were not registered as members of the Democratic Party.
The Sanders team wanted the rules changed to accommodate their delegates. The Clinton team refused. Then all hell broke loose.
During the proceedings, party leaders, including US Senator Barbara Boxer of California, were roundly booed by Sanders faithful. Scuffles broke out. Chairs were brandished. Police eventually had to clear the Las Vegas casino convention site.
Later that night Sanders supporters circulated the contact information for state party chair Roberta Lange, who was subjected to harassing calls and emailed death threats. The party headquarters was chalked with angry condemnations.
The irony is that the weekend battle in Las Vegas was over a shift of two bound delegates - at most - out of the 35 total allocated to represent the state at the national convention.
Mrs Clinton currently leads Mr Sanders nationally by 282 delegates and only needs 141 more to clinch the nomination with slightly over 1,000 left to be determined, assuming the "super delegates" - party functionaries and officeholders - who currently support her stand by their endorsements.
For Sanders backers, however, the events in Las Vegas are about more than just a skirmish over a handful of delegates.
"All of this happened because there has been a bit of a misunderstanding between the 'Democratic' Party and ourselves," writes progressive blogger John Laruits. "They've been labouring under the impression that we - you know, the people - are supposed to subserviently accept what the Democratic Party officials have decreed, but - meanwhile - we (having been misled by the word "democratic" being in their name) thought that we would get to have a say in choosing our nominee for president."
They see a nomination process that is tilted toward an entrenched establishment and its monied interests. In some states, like New York, they condemn registration rules rigged against greater voter turnout. In others, like Arizona, their issue is with perceived fraud or mismanagement at polling places.
All the while they watch as their candidate racks up win after win - most recently in Indiana and West Virginia - and make little progress toward cutting into Mrs Clinton's lead.
Whether these complaints are justified or not - and Mrs Clinton has, in fact, received millions more votes than her rival - it raises the question of whether the party will be able to pull together to face Donald Trump in the autumn or if more acrimony is in store.
Mrs Clinton would have to win more than 60% of the remaining pledged delegates to enter the convention without having to rely on her super delegate support to push her over the top. If Mrs Clinton falls short, Sanders supporters would likely up the pressure on those unbound delegates to back their man and decry what they see as party elders putting their finger on the political scale.
Given that the super delegates are political veterans more inclined to support a long-time Democrat like Mrs Clinton than the insurgent, until recently independent-registered Sanders, their efforts will likely be futile.
But will it be an ordered, organised, well-mannered process? Or will it look more like Las Vegas?
Nevada Democratic Party general counsel Bradley Schrager warns in a formal complaint against Sanders supporters filed to the national party on Monday that it could be the latter.
"The tactics and behaviour on display here in Nevada are harbingers of things to come as Democrats gather in Philadelphia in July for our national convention," he writes. "We write to alert you to what we perceive as the Sander campaign's penchant for extra-parliamentary behaviour - indeed, actual violence - in place of democratic conduct in a convention setting, and furthermore what we can only describe as their encouragement of, and complicity in, a very dangerous atmosphere that ended in chaos and physical threats to fellow Democrats."
So far the Sanders campaign has been walking a fine line between disavowing the unruly actions and acknowledging the anger their supporters feel at the process.
"Our campaign of course believes in non-violent change, and it goes without saying that I condemn any and all forms of violence, including the personal harassment of individuals," Mr Sanders wrote in a statement.
He said implications that his campaign has a "penchant for violence" were "nonsense" and went on to accuse the Nevada Democratic Party leadership of using "its power to prevent a fair and transparent process".
"The Democratic Party has a choice," he said. "It can open its doors and welcome into the party people who are prepared to fight for real economic and social change - people who are willing to take on Wall Street, corporate greed and a fossil fuel industry which is destroying this planet. Or the party can choose to maintain its status quo structure, remain dependent on big-money campaign contributions and be a party with limited participation and limited energy."
The Sanders release, which did not directly address the death threats and allegations violence on Saturday, did little to smooth over raw emotions.
Nevada Senator Harry Reid, who calls the shots in the state party and leads the Democrats in the US Senate, said the statement was "silly".
"Bernie is better than that," he told CNN. "I thought he was going to do something different."
Meanwhile, presumptive Republican nominee Trump waits in the wings - and is even egging the Vermont senator to bolt his newly adopted party and launch an independent bid for the presidency.
"Bernie Sanders is being treated very badly by the Dems," he tweeted on Monday. "The system is rigged against him. He should run as an independent!"
Such a development would greatly improve the New York real estate mogul's chances at winning the White House, of course.
"Trump obviously would like a third-party candidate on the left so that he could try to divide the vote and win," Sanders campaign manager Jeff Weaver said when asked to response to the Trump tweet. "But I think what you're going to see is unity to defeat Trump."
There were scant signs of that in Nevada, however.