I feel like the national party largely left organizing to Harry Reid's machine. Reid was a master at getting members of the Culinary Union (many of whom are non-college Latinos) to turn out for Democrats. He is a major part of the reason Democrats have been so successful in the state in the past few cycles.
But the state party was recently taken over by DSA types and the man himself is now dead. So the future of the machine is now in question.
I agree that they shouldn't get cocky and the progress they've made could easily slip.
Ye in 2018 Rosen’s campaign was run almost exclusively on an anti-Trump message pretty much, and winning by 5% really isn’t that impressive considering it was a D wave. Dems seem to think that they just “have the votes” in Nevada to he merely anti-Republican, when I think the state party needs more of a message themselves