This exercise is to visualize real geographical maps in R and then classify it by states or counties. We also can continue to build more on the same as we progress with map building, with other possible variations.
Ref: http://eriqande.github.io/rep-res-web/lectures/making-maps-with-R.html The above link is what taught me the map method and I am working on it to reproduce the results and build more on the features.
Data points needed to do the research is shared seperately. Population/ area level info for analysis can be obtained through wikipedia or using this link -https://www.california-demographics.com/counties_by_population.
Update: Unlike in the past, the data for ggmap for available to developers for free without any constraint. Now, we have to register with Google to use the APIs for locations/maps. Details are available in a seperate file.