It now appears that at least one pollster
of the 2015 Louisiana gubernatorial contest figures a different electorate than
recent trends suggest on which other pollsters base their samples. If he is
correct, the contest’s dynamics differ from what commonly is believed.
Market Research Insight has polled
monthly on behalf of a small group of subscribers. A portion of the proprietary
information gets leaked from time to time and made
some news last month when it gauged a neck-and-neck race between Sen. David Vitter and Public Service
Commissioner Scott Angelle. This was
contrary to every other poll from several other outfits that consistently have
Vitter and state Rep. John Bel
Edwards, the only Democrat in the race, leading the pack considerably over
Angelle and the other Republican, Lt. Gov. Jay
Dardenne. The MRI poll basically replicates other polls’ results on the
placements of Edwards and Dardenne when assigning 90 percent of the total black
vote to Edwards and the remainder proportionally to the others.
That July poll truly resided as an
outlier as polls immediately before and after it showed clear Edwards/Vitter
and Angelle/Dardenne tiers. It was speculated previously that the differences
could come only from two sources, one being that particular MRI poll suffered
from an “unhappily randomized” sample. Simply, it could have been an instance,
with most pollsters choosing to risk this degree of inaccuracy, where the five
percent chance of drawing an unrepresentative sample of the population actually
did occur.
But the August
results ended up fairly close to those of July for MRI and again deviant
from all others. This means the unhappy randomization scenario is highly unlikely,
as the odds of that occurring are 400 to 1. Instead, it points to the other possible
explanatory reason, the actual sampling frame used.
As previously noted in this space,
MRI’s July poll sample disproportionately picked up people registered as
Democrats and those who registered under that label, probably decades ago, but
who do not vote consistently Democrat, if even a majority of the time, and
thereby perceive themselves as independent. It overweighed Democrats by six
percent among current registrants and underweighed by a couple of points no
party (which includes people who call themselves “independent” or another party
label) registrants. This creates a sample on face characteristics more likely
to vote for Angelle, at the expense of Vitter.
While the internal numbers of the
August poll are not yet in the public domain, pollsters rarely make more than
minute shifts in their sampling frames during the course of a campaign, so it’s
probably pretty much the same as in July. If so, this means MRI is making a
radically different bet on the composition of the electorate in October, to the
favor of Angelle and disfavor of Vitter.
And if this is the case, then it’s
a controversial decision. Recent history suggests that fewer Democrats and
slightly more no party adherents and Republicans will turn out than the MRI model
assumes. That doesn’t necessarily mean it’s wrong – we won’t know that answer
until shortly after election day upon releasing of turnout statistics – but it
definitely goes against the grain.
In the meantime, this information
may make a difference in the campaign dynamics. Candidates and groups
supporting or opposing them plot strategy relative to where they think their
preferred candidate is in the field, such as if they engage in negative advertising,
how much of it, and against whom. It likely will not affect much, if any, the
actual candidates’ campaigns as undoubtedly they all do their own internal
polling and base their decisions on those. But organizations unaffiliated with
them may not have the resources to do this, and so may take cues from polling
information in the public domain.
So this divergence of opinion adds
a little to reporting of a contest that, to date, has lacked drama. Depending
upon what the final polls of the respective organizations turn up, somebody’s
going to be right and somebody’s going to be wrong in their educated guesses
about the electorate’s composition in the general election.
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