If Romney wins New Hampshire and then Huck beats him in Michigan.

Think about it. If McCain beats Mitt in NH, Michigan won’t matter terribly much to anyone except Romney. He’ll have to have it to remain viable. If he takes it, it’s good news for Fred: That’ll give Mitt, Huck, and Maverick one primary each headed into South Carolina with no strong momentum for anyone. If McCain surprises and takes it, he’ll have won two states in a row and will be surging hugely. If Huck takes it, McCain’s not badly hurt since his numbers in the state are in single digits and no one’s counting on him to win, the New Hampshire bounce notwithstanding. He’d go on to SC and beat the war drum to try to stop Huck there.

Mitt’s actually leading in Michigan, though, so another Huckabee surprise — on the Romney family’s front lawn, as it were — would be crushing, especially if it followed a Mitt win in New Hampshire. It’d be taken as proof that Romney can’t beat him where the two are competitive, even coming off a bounce. Having at that point defeated Romney twice, Huck would not only have huge momentum among social cons, he’d finally look serious enough to pick up a few key evangelical endorsements (Dobson’s maybe) and then go to South Carolina expecting to leverage the state’s evangelical base and finish off Mitt and Fred. It’s not far-fetched; he already leads there. If he pulls it off, it’s on to Florida with nothing in his way except Giuliani. He’s within seven points in that state as of this writing, and that doesn’t take into account his Iowa win.

Starting next week, the hard calculations will have to do with who should drop out and when. If McCain loses New Hampshire, he might follow Fred’s lead and try to linger on to South Carolina out of pride. Romney has the money to linger on until Big Tuesday on February 5. The more of them that stick around to split votes among themselves, the better positioned Huck is. For instance, if the nightmare scenario holds, you’ll have Mitt and Fred and possibly even McCain competing for social con votes in SC on the 19th. How do the 60% of anti-Huckabee conservatives break there? 15%, maybe, for Maverick’s stalwart war support, 15% for Fred’s true conservatism, and 15% for Mitt after having been inundated with so many Romney ads that they’ve given up resisting. The other 40% go to Huck. As such, you should think very carefully about whether Fred (or Mitt or McCain) staying in is a good move, whatever sentimental inclinations you may have to the contrary. The time to pick a consensus anti-Huck candidate could arrive as early as the evening of the 15th, when the Michigan results come in. Choose wisely.

Exit question: Unless Huck fails to win another primary before Florida, isn’t the other big winner last night Giuliani? There’s going to be a SECOND LOOK AT RUDY! in a major way if Huckamania rolls into late January. Expect to see lots of terror talk from him over the next three weeks to try to unite the anti-Huck conservatives under the banner of keeping a guy who wants to apply the golden rule to Iran far, far away from the levers of power.

Update: The counterargument, I guess, is that conservatives would much rather take their chances in South Carolina with a well funded Romney than with McCain, even if Mitt were to suffer two meaningful losses to Huckabee before then. I think the media afterglow for McCain following a win in New Hampshire would be worth more than the ads Mitt would have to run to undo media gloom following a loss to Huck in Michigan, but I can see it the other way. The long and short of it is that if Huck wins South Carolina then Rudy becomes the conservatives’ last stand no matter who wins New Hampshire.

Update: Barring the sort of three-way split among the early primaries that I described in above, the only way for Fred to win SC is in a two-man race, where the various parts of the “true conservative” base might coalesce behind him. Otherwise they get split off — if Huck’s still in it, some of the evangelicals go to Huck and if Mitt’s still in it some of the social cons are wooed by his advertising. There’s no scenario at this point in which a two-man race happens, though. The only guy who could have knocked everyone else out before SC was Romney, and even if he had, do you really think Fred was going to beat Moneybags coming off two or three primary wins?

Update: Reader Land Johnston notes that McCain may not be nearly as far behind in Michigan as thought. In one (sketchy) poll from December, with Democrats and independents included, he actually led. I think the fact remains, though, that he could walk away from a Michigan loss much more easily than Romney could, not only because of the family pedigree there but because Romney’s led in the state for so long that the only possible narrative coming out would be crash and burn. McCain’s narrative would be late surge that fell just a little short.

Update: Kerry Howley says Huckabee’s doomed on February 5 come what may. Not enough money or organization to compete with the big boys — which was supposedly also why Mitt was going to win Iowa, as I recall. Under the nightmare scenario, McCain and Fred will be long gone by Big Tuesday and Romney will have been hobbled by a string of primary losses (unless he surprises in Florida). Is Rudy’s ground game really that good? And are there really so few evangelicals in the Big Tuesday states to matter?

If Huckabee takes Iowa and does well in South Carolina, a scenario that seems increasingly plausible, he’ll have to wage a campaign built on something more than personal charisma and O’Reilly appearances. The other candidates have anticipated this moment, building organizations in states that will matter beyond January. Huckabee has not. He’ll be a little-known candidate with a shoestring budget relying on dated grassroots political strategy as an air war rages between better-funded candidates.

It’s a recipe for failure.