Despite protestations to the contrary, I'm pretty sure thatRudy Giuliani's decision to skip the Ames straw has quite a bit to do with the challenge of winning Iowa in January. Giuliani wants Iowa to matter less.

Winning Ames costs, literally, millions of dollars. All those buses, hotel rooms, bands, light shows, chow, swag. Millions that Giuliani would rather spend in Florida. Or on organizing actual caucus-goers in January. Or in New Hampshire.

To imply, as Giuliani's campaign manager did, that the resources allocated to Ames are separate from the resources allocated to winning the caucus, is a stretch. Contacting, persuading and cajolling 15,000 conservative Iowans to spend their Saturday in Ames is not a wasted expense. I can't put an exact percentage on it, but I'd guess that more than half of Ames attendees eventually caucus. Giuliani is, in essence, writing most of them off.

Giuliani's support in the state is not unimpressive, but it is shallow, and if Iowa is determined by the political/media establishment to be Judgment Day, the probability that Giuliani will win the nomination drops.

Here's Giuliani's primary strategy in a nutshell: win (or place) in New Hampshire and Nevada, win in Florida, catapult to the February 5 states with the delegate lead and Florida momentum, and cruise to the nomination.

For the frontrunner to dismiss Ames as just another straw poll is an astonishing, but perhaps necessary display of hubris -- one that stems from both strength and weakness. It's from strength that Giuliani has the ability to single-handedly mess up those rivals of his who are banking on an Iowa-based strategy. It's from weakeness that a Northeastern cultural liberal (albeit a reformed social conservative) has to skip the conservative caucus vetting procedure that has dimmed lesser lights.

John McCain's campaign will now feel cross-pressures; he could spend more and prove to Iowans that he's serious about winning the state by polling well in Ames; or he could follow Giuliani and reduce his footprint. TBD.

Mitt Romney's national campaign strategy is predicated upon a win in Iowa; and its win in Iowa is predicated upon a strong showing in Ames. If Ames is suddenly less important because the frontrunner won't show up, then a Romney victory there is considerably less impressive.

"We shouldn’t be disqualified or criticized for their campaign strategy and tactics," a Romney adviser insisted to me this morning.

Advisers to Fred Thompson have told me that it's unlikely that the actor-cum-Reaganesque presence would mount a full scale Ames campaign, but perhaps Rudy's exit gives him an opportunity to organize, quickly, and turn Ames into his first surprise showing. TBD.

Newt Gingrich will attend -- but he won't try to game the thing.

The trick here is for DuHaime and other Giuliani advisers to convince Iowa and the press that Ames matters less -- Jim Nussle warned that it could diminish Iowa's status, somehow -- so often do events like Ames wind up mattering only because the national political media decides that they are thresholds to the nomination.

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