Newt Gingrich and Rick Santorum’s “Anti-Romney Vote” Hardly Registers

“When you take all of the non-Romney votes, it’s very likely that at the convention there will be a non-Romney majority,” said one candidate vying to claim that majority.

“It’s always harder when you’ve got two conservatives running in the race,” said the other. “We have the anti-Romney vote, if you will.”

But the anti-Romney candidate is a lot like the Highlander. There can be only one, and it is an entirely fictional creation.

Despite the respective calls by the Gingrich and Santorum camps for the other to get out of the race so the two can stop splitting the anti-Romney vote, there have been only two states that Romney won where the combined vote of the two would have been decisive—Michigan and Ohio—and in both of those state it would have shifted only a few delegates.

In what are expected to be tight three-way contests in Mississippi and Alabama today, Santorum and Romney are neck-and-neck. But even if Gingrich were to exit, the two would still be neck-and-neck. A poll conducted this weekend by Public Policy Polling (PDF) shows Romney leading Santorum by 1 percentage point. When the same respondents were asked who they would support if Gingrich were not a candidate, the results hardly change: Santorum takes a 3-point lead—still within the poll’s margin of error.

The lack of a unified anti-Romney vote has also been borne out in polls in Michigan and in Ohio, showing Romney was the second choice of Gingrich and Santorum voters.

While polling numbers suggest Romney’s margin would tighten somewhat in a one-on-one race against Gingrich or Santorum, looking backward even if Santorum and Gingrich’s votes had been combined, it would have swung just a handful of delegates, and not a single winner-take-all state.

Voters who back Gingrich because they think he is a strong conservative might migrate to Santorum. But those who support him because of his experience as speaker of the House and his much-touted debate ability might prefer Romney. Perhaps the Romney camp is onto something when it calls the idea of an anti-Romney vote “completely ridiculous,” as campaign spokesman Ryan Williams put it.

In a sense, the idea of an anti-Romney vote gives him too much credit: It assumes that Republicans are making their decision solely based on what they think of Mitt Romney.