Joe The Plumber's Confusing Advertising

So, I was perusing this very interesting article by Matt Lewis at The Daily Caller and when I scrolled down the page I saw this advertisement:

Now, if you'll note the image contained in that ad, Mr. The Plumber is standing and chatting with then-Presidential -candidate Senator Barack Obama. Obama appears to be, well, lecturing the plumber-turned-Congressional candidate.

My question: Why use an image that includes President Obama? Ostensibly, Samuel "Joe the Plumber" Wurzelbacher is running as a darling of the Tea Party, right?


So, why would a rabid anti-Obama candidate for Congress use an image of said candidate and Obama?

Seriously. I'm really asking.