I never got this either especially with the high Latino population.
Latino != Democratic. The best example of this was the presidential election this year in Florida.
Latinos in FL are more varied in terms of ethnicity/nationality.
Most Latinos in NV are of Mexican ancestry. Mexican-Americans are generally among the most pro-Democratic Party voter base. However, obviously, Mexican-Americans aren't monolithic at all and Clark County, NV isn't just Las Vegas.
Imperial County, CA, Santa Cruz County, AZ, New Mexico, and the Rio Grande Valley beg to differ.