Scenario #2. Mr. Romney finishes second behind an insurgent candidate. This scenario is still a pretty good one for Mr. Romney. Most notably, he’ll have beaten Mr. Pawlenty, who will have finished no better than third place in a state that had seemed pretty strong for him. None of the insurgent candidates, even after winning Iowa, are liable to be terribly competitive among the moderate voters of New Hampshire, so Mr. Romney will still be on track for a win there.

That’s not to say that there would be no benefit at all to Mr. Romney from having managed expectations effectively. Mr. Huntsman, for instance, will try to exploit this scenario — and his argument to New Hampshire voters (and Republican elites) will be more credible if Mr. Romney’s performance is thought of as having been disappointing rather than a “strong second”. But more likely, this sets up a “playoff” between Mr. Romney and the insurgent winner of Iowa in the next several states — one which Mr. Romney is likely (although not certain) to win.

Scenario #3. Mr. Romney finishes second behind an establishment candidate. This scenario is the one in which having lowered expectations might provide the clearest benefit to Mr. Romney. In particular, if Mr. Romney finished second behind Mr. Pawlenty, keeping expectations low could limit the size of Mr. Pawlenty’s bounce in the polls heading into New Hampshire. If Mr. Romney in fact prevailed in New Hampshire, the two candidates might be on a roughly even footing heading into the remaining states, with the other candidates having little chance.

The same largely holds if Mr. Romney finished second behind Mr. Perry, who is probably too conservative to be a favorite in New Hampshire even if he wins Iowa. If Mr. Romney’s second-place finish were perceived as credible rather than disappointing, that could make it more difficult for a candidate like Mr. Huntsman (or even Mr. Giuliani) to emerge as the moderate alternative to Mr. Perry with a strong showing in New Hampshire.