Skip to main content
ABC News
Gingrich Tied With Romney in South Carolina Forecast

The question I posed on Wednesday — does Newt Gingrich have momentum in South Carolina? — now appears to have an unambiguous answer. Yes, Mr. Gingrich does have momentum — and a lot of it.

Six different South Carolina polls have been released so far on Thursday, and they show a split in their results. In two traditional polls with live interviewers, one by Marist for NBC News showed Mitt Romney leading by 10 percentage points, and the other by the Tarrance Group for Politico had him ahead by 7 points.

It should be noted, however, that Marist split its results into samples conducted before and after Monday night’s debate, and found that Mr. Romney’s lead was smaller — five points — in the post-debate sample. And a third traditional poll, from American Research Group, gives Mr. Gingrich a nominal one-point advantage.

Meanwhile, three automated polls — by Rasmussen Reports, Public Policy Polling and InsiderAdvantage — have Mr. Gingrich in the lead instead, by margins ranging from two to six points. All of the interviews for these polls were conducted on Wednesday, after the debate and the qualified endorsement Mr. Gingrich received from Sarah Palin.

The FiveThirtyEight forecast model, trying to evaluate all of this information as objectively as it can, sees substantial momentum for Mr. Gingrich in South Carolina, giving him at least as strong a tailwind as Rick Santorum had in the closing days of the campaign in Iowa.

The model now shows a virtual tie in the race, with Mr. Gingrich projected to get 34 percent of the vote and Mr. Romney 33.6 percent and each candidate having about a 50 percent chance of winning.

Mr. Gingrich has gained ground in the polls more than Mr. Romney has lost it. Two days ago, our forecast had Mr. Gingrich with 22.6 percent of the vote, so he has gained about 11 points since then. Meanwhile, Mr. Romney’s projection has declined less than 3 points — to 33.6 percent from 36.1 percent — over the same interval. Instead, most of Mr. Gingrich’s gains have come from Rick Santorum and Rick Perry (who dropped out of the race today and endorsed Mr. Gingrich), as well as from undecided voters.

Our research shows that high levels of volatility and disagreement in the polls make polling aggregation methods less reliable. In other words, the margin of error on the forecast is especially high, enough so that either Mr. Romney or Mr. Gingrich could emerge with a clear victory by the time that the vote takes place on Saturday.

There are also an unusually high number of developing news stories in the closing days of the campaign, including Mr. Perry’s leaving the race and endorsing Mr. Gingrich, new ambiguity about the results of the Iowa caucuses, Thursday night’s debate and the interview given to ABC News by Marianne Gingrich, the candidate’s second wife. Although it is worthwhile to monitor the polls carefully, we will almost certainly go into Saturday evening with a lot of uncertainty about the outcome.

This may not be the time to get into a lengthy discussion about the merits of automated polls versus live-interview polls, but something to keep in mind is that automated polls usually do not call cellphones. About 25 percent of South Carolina voters do not have land lines in their homes and rely solely on mobile phones.

Automated polls also generally have lower response rates than traditional polls, which can sometimes lead them to draw the voter universe too narrowly, as they tend to get only the most enthusiastic respondents. On the other hand, enthusiastic respondents also tend to be highly informed, so the automated polls may serve as effective “leading indicators” of how the broader universe of voters will react to developing news.

Nate Silver is the founder and editor in chief of FiveThirtyEight.