Mark Blumenthal | May 5, 2008
Topics: 2006 , Barack Obama , Divergent Polls , Hillary Clinton , LA Times/Bloomberg , Mike McDonald , Pollster , Pollsters , SurveyUSA , Zogby
Time for another round-up of available poll demographics, this time from North Carolina. The most important variable in this state is the African American percentage of likely Democratic primary voters. The most recent polls -- at least among those that have disclosed their demographics -- have converged around a black percentage of 32-33%. Needless to say, given the near monolithic support that African Americans have given Barack Obama, that percentage will ultimately be critical to his share of the vote on Tuesday.
The following table shows demographic composition statistics for those pollsters that have released them. Click on the table to display a larger version that also includes the vote preference results for reach poll.
The table excludes the pollsters that have, as of yet, not publicly released demographic information for their North Carolina surveys:
Mason-Dixon, Rasmussen Reports, and LA Times/Bloomberg (special thanks to readers Paul and jac13 for sharing the demographic profile data that Zogby shares with paid subscribers).
As in previous states, we see considerable variation in the kinds of voters selected as "likely primary voters." Easily the most variant likely voter sample on the list is the one from the Civitas Institute from early April, with a composition of just 28% African American and 17% under the age of 45. However, even if we set that survey aside, we still see considerable variation: from 51% to 58% female, from 39% to 55% age 18-to-44 and from 25% to 37% African American (and those last extremes come from a single pollster -- more below).
A quick review from my post on the demographics of the Pennsylvania surveys:
It is important to remember that pollsters come to these composition statistics through different paths. Some interview samples of adults, weight those demographically to match census estimates of Pennsylvania's adults, then select "likely voters" and let their demographics fall where they may. Others will weight their "likely voter" samples directly to pre-determined demographic targets. Some pollsters will not set weights or quotas for demographics, but will set such weights or quotas for geographic regions (based on past turnout and their assumptions about what might be different this time).
With that in mind, note two very striking changes from two pollsters that set pre-determined demographic targets, Public Policy Polling (PPP) and InsiderAdvantage:
- The first three surveys released in April by PPP had an African American composition of 36% or 37%. Their most recent survey, fielded last Sunday and Monday evenings, had a black composition of just 33%.
- The gyrations in the weighting by InsiderAdvantage are even more dizzying. Their first North Carolina survey in late March was 37% African American. Their next two surveys in April were only 25% African American, and their most recent poll last week bumped the black percentage back up to 33%. Notice that none of their percentages for women, 18-29-year-olds, 18-44-year-olds or those 65+ changed by a single digit, despite a 12-point variance in the black percentage.
Both pollsters put out written summaries of their results, but neither made any reference (that I could find) explaining or justifying their changing assumptions about the racial composition of the North Carolina electorate. [Update: On their final poll, PPP upped the black share to 35%, but explained their rationale]. By the way, we know that these two pollsters set predetermined demographic targets, because both have confirmed as much to me in previous communications (here for InsiderAdvantage and here for PPP).
The change in the PPP poll is important -- they should have noted it -- but relatively modest compared to the astonishingly large, significant and unexplained shifts in the African American composition in the InsiderAdvantage polls. InsiderAdvantage's Matt Towery likes to brag of his "significant experience" as a pollster, but after a number of curious episodes over the last few months, it is getting very hard to take those claims seriously.
It's also worth pointing out the relative stability in the racial composition of the SurveyUSA results, given that they do not force their samples to a pre-determined demographic profile (details on their procedures here). The percentage of African Americans in their four surveys since March have remained relatively stable, falling within the range of 30% to 33%.
Finally, one caution about the percentage reported as "unaffiliated" (having no party affiliation). Only PPP includes the full text of their party question, and it is possible other pollsters are asking about party identification (whether respondents "consider themselves" as partisans) rather than party registration.
Update: Almost forgot. Fivethirtyeight's Poblano posted a handy spreadsheet that can help you see just how much small changes in the racial composition of the North Carolina electorate can affect the potential margin between the candidates. It's well worth the click.
Update II: In posting this last night, I neglected to point out that North Carolina has been releasing reports on the demographics of early voters. As North Carolina is one of nine southern states still required by the Voting Rights Act of 1965 to track voter registration by race, racial tallies among early voters are also available. The demographic composition of early voters have been analyzed by Brian Schaffner, DailyKos diarist dean4ever and noted in comments by many of our readers over the weekend.
North Carolina is an exceptional state in that it provides near real-time updates of its voter registration file. Indeed, you can download the entire file of absentee and early in-person voters directly from the state's ftp site.
North Carolina is also an interesting state because race and gender are recorded on the voter file (birthdate appears to be supressed in the absentee file). When I crunch the numbers, out of the 397,850 persons who are listed as returning a Democratic Party ballot as of 5/03:
39.9% are African American
60.8% are women
Note, a small percentage (less than 1%) of records have missing data.
Will these percentages hold for Tuesday? That is hard to say, mostly because people who study early voting (myself included) don't know much about the characteristics of early primary voters. Added is the confounding factor that one-stop registration and voting is permitted for in-person early voters only and not for Election Day voters. Providing little further clues, African-Americans are only slightly more likely to vote early in-person, 40.6%, and women slightly less, 60.7%.
The fact that nearly 400,000 early votes have been cast so far is remarkable given past primary turnout in North Carolina. The state held a caucus in 2004 (due to a redistricting battle that delayed the primary), but 544,922 Democrats voted in the largely uncontested primary in May 2000, and 691,875 voted in May 1992 (statistics I gathered for a column noting that pollster PPP has been sampling from a total universe of 874,222). The record was 961,000 in 1984, according to the Charlotte Observer, which cites "long time N.C. political observers" guessing that "as many as 1.5 million" may vote this year. So this early vote will be a significant portion of the total votes cast, but as McDonald points out, no one knows exactly how big.
It is also worth pointing out that the Obama campaign has made early voting drives a focus of their field organizing, so it is certainly possible that the ranks of early voters are disproportionately swollen with Obama voters. Last week's poll from SurveyUSA showed Obama leading by a 18 points (57% to 39%) among early voters, but that subgroup was just 2% of their total sample. Thus, one key result to watch in the final poll releases today -- among those far sighted enough to track and report it -- will be the size and preference of the early voters.