Romney's real primary model: Michael Dukakis

In some ways, however, the Republican contest bears resemblance to the Democratic primaries of 1988. In that year, Michael Dukakis lost his fair share of states — and won very little in the South. But on Super Tuesday, three candidates — Al Gore, Jesse Jackson, and Richard Gephardt — each won Southern states rather than consolidating the vote. Mr. Dukakis was buoyed by the fact that none of them appeared to have a majority path to the nomination, even though he wasn’t winning all that many states himself.

Mr. Dukakis still had some work left to do — parrying a challenge from Mr. Jackson in New York on on April 19, for instance — but by that point the outcome of the race had become fairly clear.

Mr. Romney could follow a similar path. His case will be stronger, of course, if he also wins Ohio, a state where he still trails in the polls. In 1988, Mr. Dukakis lost most states on Super Tuesday, but he was helped by wins in Texas and Florida that may have been of similar symbolic importance.