from my experience, tourist areas seem to reflect where they get their most people from. For example the beaches of Southwest Florida seem to attract people from the same place that the Panhandle draws from. However nice beaches are expensive and draw the more international the crowd. This is where you get a lot of multicultural people, relatively disadvantaged, even if they are modestly wealthy by most standards, people and people from big cities. The Huffington Post crowd. The more regional and less expensive places tend to draw people from rural and white places where everyone makes about the same amount of money. The Trace Atkins and Fox News crowd.
This could explain in my state why Galveston is Republican leaning, and yet the beaches of South Padre Island are Democratic leaning. You're pretty right about that.
However there is a strong GOP lean on historical tourist spots.
When it comes to who is attracted to which tourist destination, historical don't matter. What matters is how diverse a place is in terms of class and race.
If its a place that generally attracts families with young kids from a couple hundred miles away to stay in 1-star and 2-star motels and motor inns from places where there is very little poverty but six figures is considered "rich" and anyone who is half-Italian is considered "ethnic", then yeah. That place will be 55%, if not 65% Republican.
Here's a picture of such a place
On the other hand, if the place generally attracts people under 35 from places across the world where the slums are right next door to $10 million dollar penthouses to either come camp right out on the beach or to stay in 4, 5 and 6 star hotels, any Republican who can get more than 40% of the vote is either the next Ronald Reagan or the biggest RINO ever.
Here's a picture of such a place