Whether they actually would/do support the team remains to be seen.  But Vegas isn't a totally transient community.  It is the 28th most populated city in the United States and has had several growth spurts in the last 20/30 years.

 

"Las Vegas was settled in 1905 and officially incorporated in 1911. At the close of the 20th century, it was the most populated American city founded within that century (a similar distinction earned by Chicago in the 1800s). Population growth has accelerated since the 1960s, and between 1990 and 2000 the population nearly doubled, increasing by 85.2%. Rapid growth has continued into the 21st century, and according to a 2013 estimate, the population is 603,488 with a regional population of 2,027,828."

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