As much as I said he was pretty obviously done, Scott Walker’s departure from the race sure seems abrupt and even premature. It’s hard to have much hope when you go from a first tier candidate to significantly under 1%. Still, not only is it early but the race is so unsettled and chaotic, couldn’t he have held out a bit longer? But David Kurtz reminds me of a key point about Walker. Going back to the early days when he was the new Governor of Wisconsin, Walker was always a creature of the Koch Brothers and like big donors. (There was actually a comical episode some of you may remember when a prankster called Walker up as “David Koch” and talking to Walker for something like an hour. He recorded the call and then made it public.)

There’s already reporting out there that Walker’s campaign was having a very hard time raising money in recent weeks. But that’s no different in itself to what we’ve seen in countless campaigns, a standard cycle. You lose traction and poll numbers, get the look of a loser, donors stop answering calls and suddenly you’re done. It is a brutal and vicious cycle, a campaign death spiral that it’s extremely difficult to break out of.

One of the premises of this campaign has been that a lot of candidates who would have had to drop out in earlier cycles will be able to hang on much longer. As long as they have their billionaire willing to fund things, they can go on pretty much indefinitely. Remember, that’s what kept Newt Gingrich in the race in 2012 – Sheldon Adelson’s cash. A similar story with Rick Santorum with his own billionaire.

But the converse is also true. I wonder whether Walker’s own attachment to Koch like mega-donors and the change in the campaign finance landscape brought about by Citizens United has shifted the terrain and forced Walker to pull the plug more rapidly than we might have expected. When the game really is controlled by a small group of billionaires, if they say you’re done, you’re done.

And he’s done.