I'd have to say Utah. The ski areas are quite "latte liberal" (as stupid of a term as that is), and obviously we know about the Republican areas.
California and Florida both have lots of suburban Republicans. They may be minorities in their counties, but they cast more votes than the rural Republicans.
Washington has a ton of moderate libertarian Democrats in the suburbs. Oregon would be a decent option, though.
EDIT: The problem with southern states is that the Democrats/liberals are often very socially conservative because they are black.
Yeah but how significant are the "ski areas" that you speak of? Where are they located and how many votes do you "attribute" to these areas?