I have seen these t-shirts for sale previously - for those who want to wear their political affiliations on their sleeve (pun intended).
The donkey, symbol of the Democrats. The elephant, symbol of the Republicans. The t-shirts denote political leanings and separate the population into potential dates or...not.
Today I found this:
Perhaps its for swinging voters (haaaaaaaaaa!!!!)
It would be fun to wear this t-shirt just to confuse everybody. I guess it opens up the field a bit...