The man from the van didn't have the right form

Yesterday, I got this email:

Subject: A great Texas Rancher analogy

While suturing a cut on the hand of a 75 year old Texas rancher, whose hand was caught in a gate while working cattle, the doctor struck up a
conversation with the old man. Eventually the topic got around to Obama and his bid to be our President.
The old rancher said, 'Well, ya know, Obama is a 'post turtle'. Not being familiar with the term, the doctor asked him what a 'post turtle' was. The old rancher said, 'When you're driving down a country road and you come across a fence post with a turtle balanced on top, that's a 'post
turtle'.'
The old rancher saw a puzzled look on the doctor's face, so he continued to explain. 'You know he didn't get up there by himself, he doesn't belong up there, he doesn't know what to do while he is up there, and you just wonder what kind of a dumb ass put him up there.'

Now where'd I see this joke before? Oh I know, this is a Bush joke with the word Bush crossed out and Obama written in crayon!
McCain supporters must be pretty desperate if they are reduced to recycling Bush jokes. I'm totally going to start selling these: