A recent poll carried out in Iraq for ABC News, USA Today, the BBC and ARD German TV had one result that seems to have gotten less media coverage than it deserves. Conventional wisdom has been that Sunni Arabs represent something like 12-22% of the population of Iraq.
Recent survey data, including this poll, have had different results. This survey found 47 percent Shiite Arabs, 35 percent Sunni Arabs, 15 percent Kurds and three percent others.
D3 Systems reports that in its previous surveys it has seen Shiite Arabs in a range from the high 40s to low 50s, and Sunni Arabs in a range from the high 20s to mid-30s. The 35 percent Sunni Arab estimate in this poll is at the high end of its previous data, but within that range. This poll had more sampling points than any previous individual national study in Iraq by D3/KARL
Another large poll, carried by ORB gave similar results: 32% Sunni Arab, 42% Shiite Arab, and another 9% Arabs who didn’t identify their sect. It turns out that the lower estimates, while widely quoted, don’t seem to have a lot of sourced evidence behind them.
As far as we have been able to ascertain there is no official Iraqi estimate of the country's Sunni vs. Shiite Arab populations, and no single authoritative source of empirical data on the subject.
Needless to say, if these numbers are correct and previous Western estimates wrong, they should radically alter our view of likely outcomes in a sectarian conflict in Iraq. If Sunni Arabs there have a population that is 75% of the Shiite population rather than 35%, the decision of insurgents to provoke sectarian conflict begins to seem much more rational.