Rush Limbaugh is unbashedly taking credit for former New Mexico Governor’s Gary Johnson’s killer joke at last week’s GOP debate (“My next-door neighbor’s two dogs have created more shovel-ready jobs than this current administration”)—and by and large the media have agreed that Rush owns the knee-slapper when, in fact, some unfamous person coined the crack years ago.

Not the biggest media news of the day, but it is typical of how my dog digs deeper into stories than this current Beltway press.

Rush spent a full five minutes on the radio yesterday magnanimously forgiving others for inadvertently borrowing from him. For how could they not?

It’s very difficult for any other conservative out there to be considered original with me on the scene. So I cut all these people slack. They steal stuff from me all the time…. it’s something that can’t be avoided. You go out there, and you speak for fifteen hours a week, and you’re sucking up a lot of oxygen, a lot of opinion, it’s going to be very tough for anyone else to be original.

A bit of background: Rush did indeed crack a variation of the doggy line the afternoon of Thursday evening’s debate; Johnson later explained to Huff Post that he received the one-liner from a radio host friend that day and didn’t know of Rush’s wisecrack. And most media, like Rush, let the impression stand that Johnson haplessly crossed the border onto Limbaugh property. You can hear some of them on the audio:

But Rush no more created the joke than Johnson did. Or than did Johnson’s radio host buddy. Or than did financial blogger Jeff Carter, who ran with the joke a full week before Rush, and immediately explained that he got it from “some commentary on the Internet.”

As Talking Points Memo showed (and as I relayed last week), the shovel-ready bit has been out there not for a couple weeks, but for a couple years. A TPM slideshow of the “Top Ten Protest Signs of 2009,” includes a photo, taken at a Tea Party rally, of a black dog wearing a red vest that reads: “I Create Two Shovel-Ready Projects/Day.”

Obviously, the joke began soon after Obama’s stimulus program memed-up “shovel-ready” into the atmosphere in early 2009. But most media found it easier (and, considering Rush’s wrath, safer) to grant Limbaugh authorship than to follow the TPM lead.

Media people of all people should know that catchphrases, one-liners, spin and falsehoods travel at the speed of lite, and for one borrower to claim creation while cutting another borrower “slack” is a pile of poop the press should promptly scoop up.