The conventional wisdom holds that the periodic rise and fall of various conservative or outside challengers to Mr. Romney — Newt Gingrich, Rick Santorum, Herman Can, Gov. Rick Perry of Texas — is a sign that Republican voters have aligned into “Romney” and “Not Romney” camps. Further, it claims that Mr. Romney is benefiting since two of the “Not Romney” choices, Mr. Gingrich and Mr. Santorum, remain available to Republican voters.
The polling data on this is more ambiguous. As Lynn Vavreck and John Sides noted in January, polls have sometimes shown that many of Mr. Gingrich’s supporters list Mr. Romney rather than Mr. Santorum as their second choice, and that many of Mr. Santorum’s supporters prefer Mr. Romney to Mr. Gingrich.
But when it comes to the actual behavior of voters once they get around to voting in each state, the evidence seems to be on the side of the “Anybody but Mitt” theory.
Take a look at what the polls are projecting right now in Georgia, Oklahoma and Tennessee — three Southern states that will vote on Super Tuesday. (Virginia will also vote, but only Mr. Romney and Mr. Paul are on the ballot there.)
In all three states, Mr. Romney is running in second, and he has an almost identical percentage of the vote in each one: he projects to receive 27 percent of the vote in Georgia, 28 percent in Oklahoma, and 30 percent in Tennessee.
But while Mr. Santorum is running ahead of Mr. Romney in Oklahoma and Tennessee, in Georgia it’s Mr. Gingrich with the lead, who long made his home there and so has a unique advantage in the state.
Mr. Romney could be harmed, of course, if one of the opponents — probably Mr. Gingrich — were to drop out. But a win in Georgia for Mr. Gingrich — our model has him as a substantial favorite there — could give him some justification for continuing his campaign. Alabama and Mississippi vote on March 13, where Mr. Gingrich could seek to re-assert himself.
If Mr. Gingrich failed to win either of those states, perhaps he would consider dropping out then. But at that point, about half the states will already have voted, and Mr. Gingrich will have accumulated some delegates, the majority of which might have wound up in Mr. Santorum’s hands.
Of course, some of those delegates could still wind up with Mr. Santorum if Mr. Gingrich were to endorse him after dropping out — rules about what delegates are allowed or obliged to do under these circumstances differ from state to state.
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.