[..] you could call it the New York City problem -0,01% of the area but 2,7% of the population.
A suggested better representation is using bubbles with sizes proportional of the number of votes, ending with this map showing more correctly a majority of blue instead.
Visualization is growing in importance nowadays that we have so much data all around. Visualization can help to identify trends, to find patterns, to show relations between data. It can show what the data represents, putting it in an intuitive way.
But as this article shows, used in a wrong way, visualization can mislead you just as well.
To be on the safe side, it’s better to check the numbers or data behind the representation in order to confirm what the image is showing you … or if somebody is not tricking you!