Michael Gerson believes that economic anxiety will drive Republican voters to support Romney:

But Romney has a better case in a time of economic fear — like the one we may be entering — when competence becomes a desperate political demand. In this case, Republicans may choose, once again, not the purist they love but the old hand they trust.

It is likely that enough Republicans will turn to Romney for him to win the nomination, but this explanation as to why they will doesn’t seem very persuasive. What Gerson doesn’t address is that Romney isn’t “the old hand” Republicans trust. Romney isn’t a trustworthy candidate. If the GOP follows its typical pattern and nominates him despite this, it won’t be terribly surprising, but it won’t be because he inspires very much trust.

It’s also not clear that economic fear and anxiety drive voters to what Gerson calls the “reassuring center.” That doesn’t seem to be true in general elections, unless we automatically identify the eventual winner as the candidate of the “reassuring center,” and I don’t think it always holds true in Republican nominating contests. Certainly, insurgents from right and left failed to topple sitting Presidents who were seeking re-nomination, but it was the incumbents’ vulnerabilities that made these challenges from inside the incumbent party possible. The conditions that made primary challenges possible also led to the incumbents’ defeat.

In an open field during poor economic times, Republicans once opted for the candidate who was both familiar and relatively more conservative than the main competition. The Bushes and Doles have typically won their nominations when economic anxiety is not so great, which suggests that Republicans usually prefer more bland nominees in good times, but they may be willing to gamble on a perceived ideological candidate when economic conditions are poor. What Gerson is proposing is that the party out of power will opt for the “safe choice” in tumultuous times, but this only makes sense because Republicans have usually preferred the “safe” or at least familiar candidate regardless of economic conditions.