It's worth stressing that while Sanders is in the catbird seat for getting the nomination it is not because he is drawing overwhelming support from voters. Though he is doing very well, the most salient reason why he is in such a dominant position is the incredibly fragmented nature of his opposition.
The Nevada numbers are striking in this regard. First, take the overall vote numbers. In 2016, Sanders, judging from the 2016 entrance poll, had around 46 percent of the first preference vote and wound up with 47 percent of the county convention delegates. This time around he had around 33 percent of the first preference vote....and got 46 percent of the county convention delegates.
Looking at the entrance poll breakdowns in 2016 and 2020, Sanders did indeed do very well among Latinos this year, receiving 51 percent support. But in 2016, he received 53 percent, so Sanders held his 2016 support among this group--impressive in a multi-candidate field--but he did not increase it. Similarly, Sanders received 27 percent black support this year, an increase, but not a large one, over his 22 percent support in 2016.
As these figures imply, Sanders did considerably less well this time around among white voters. In 2016, he was supported by 49 percent of whites; this time he drew only 29 percent support. Breaking this down by education, he fell from 46 percent in 2016 to 24 percent among white college graduates and from 52 percent to 35 percent among noncollege whites.
In light of the Nevada results, it certainly seems like the non-Sanders elements of the party could prevail against him if they unified against him. But that does not seem likely to happen anytime soon; the next contest is in South Carolina and no one seems in any hurry to drop out. Indeed the contest will include the ludicrous candidacy of Tom Steyer, who could draw as much as 18 percent of the black vote. Then it's Super Tuesday with the other billionaire doofus, Mike Bloomberg, in the mix to further fracture the non-Sanders vote.
Now, if you are bullish on Sanders' chances to beat Trump, this is a perfectly fine development. But if you are very doubtful of his chances. this could be a disaster in the making. In the latter case, you are at the mercy of the wisdom of the various non-Sanders candidates and their ability to clearly assess the political situation.