Understanding the Polls on the Iran Deal

By Mark Mellman

The Hill

July 28, 2015

How can Americans favor the Iran deal by 18 or 19 percentage points and oppose it by 8 or 10? 

They can’t. 

Yet, in recent days, leading pollsters have offered all of those results.

The usual explanations don’t suffice. These differences aren’t within margins of error. They don’t reflect variations in sampling methods. These are differences not just in degree, but major differences in kind.

They are differences I believe come down mostly to the questions asked. 

If poll questions argue, in effect, that it’s a good deal, Americans tend to support it. When people are asked their opinion in an unbiased way that reflects their own understanding of the agreement, they oppose it.

Consider the questions. 

The Washington Post poll explains the agreement in terms most people would support: “a deal to lift economic sanctions against Iran in exchange for Iran agreeing not to produce nuclear weapons. International inspectors would monitor Iran’s facilities, and if Iran is caught breaking the agreement, economic sanctions would be imposed again. Do you support or oppose this agreement?”

In short, the question posed by the Post presupposes the elements of a pretty good deal and produces a 56 percent to 37 percent majority in support. 

YouGov’s poll also assumes a positive outcome, though its description is more sparse: “Several world powers, including the United States, have reached an international agreement that will limit Iran’s nuclear activity in return for the lifting of major economic sanctions against Iran. Do you support or oppose this agreement?”

Respondents are told the agreement “will limit Iran’s nuclear activity.” This less fulsome, but still positive, description produces a slightly smaller 51 percent to 33 percent majority in favor of the agreement.

What about poll questions that offer no assessments of the content or effectiveness of the agreement and just ask Americans’ opinions? They find majorities opposed.

Pew asked simply, “From what you know, do you approve or disapprove of this agreement?”

Relying on their own perspective, unaffected by a positive description of the deal, just 33 percent approve, while 45 percent disapprove. Among the 79 percent of the public that has heard something about the agreement, 48 percent disapprove and 38 percent approve.

The most recent poll, released Tuesday by CNN/ORC, gave voters a bit more guidance on the content of the agreement than Pew did, but it used more neutral terms than those offered by the Post and YouGov while also focusing on Congress’s role.

“As you may know, the U.S. Congress must approve the agreement the United States and five other countries reached with Iran that is aimed at preventing Iran from developing nuclear weapons. … Do you think Congress should approve or reject the deal with Iran.”

Here the agreement merely “aims” at preventing a nuclear Iran, rather than positing it “will limit Iran’s nuclear activity,” as YouGov stated.

As a result, the CNN/ORC poll also finds a majority urging Congress to reject the agreement 52 percent to 44 percent.

In short, every poll that finds support for the Iran agreement includes a question that explains why people should support it while casting no doubts. Every poll that offers a neutral description, or none at all, finds Americans opposed to the agreement.

Thus, a fair interpretation of the data suggests Americans’ natural inclination is to oppose this deal, though they would support an agreement they believed would accomplish supporters’ goals.

Every poll indicates Americans don’t believe this deal will work.

The Washington Post poll, which found majority support for an agreement described in positive terms, also found that 64 percent are not confident “that this agreement will prevent Iran from developing nuclear weapons.”

Similarly, only 23 percent in the YouGov poll express confidence the agreement will have the desired effect.

Americans would favor an agreement with Iran that worked. Most doubt this one will. 

Mellman is president of The Mellman Group and has worked for Democratic candidates and causes since 1982. Current clients include the minority leader of the Senate and the Democratic whip in the House.