This one must have slipped past you in late January. Thats when I first heard it.
Makes me cringe a bit... but I suppose the gardener could get a new job as a silent horn on one of the security vehicles. People could look at him tied on there and say, "Honky! Honky!" as it drove past...
This reminds me of my all time favorite wrong answer on Jeopardy by Mormon conservative Ken Jennings. He shoulda got credit for it.
Seriously though, it does bring up the point that, save for the c...r of his s..n, the Big O seems to be as 'w...e' as can be (let's see if I fooled the robot there). I have no idea about Mrs. O, except that the 'hoe' part doesn't seem to fit her, and that at the same time she is not a likable person.
Dale, it shouldn't make you cringe at all: the joke is precisely on those who classify people by groups, and use various code-words to identify them. Just another case of idiots who hijack the language to a point where us regular gardeners can't use it anymore.