As I may have mentioned once or twice in this blog, a single poll is not enough to set one’s hair on fire. With polls and surveys, it is trends that matter.
I wish more news organizations paid heed to that mantra (“it is trends that matter”) rather than scream from the rafters over the latest national poll (and see my thoughts here about the idiocy of national polls) results or wrote click-bait headlines how one single poll shows that the presidential contest between Hillary Rodham Clinton (Democratic Party) and Donald John Trump (Republican Party) is tightening up, a nailbiter, or neck and neck.
I will grant that a survey that seems to go against the historical grain may be worthy of the attention of news outlets, but is such attention always deserved? This post is the first in a series that looks at the “One-Offs”, those state polls that seem to go “zig” when all the other surveys go “zag”.
Today’s initial post takes us to the state of Oregon. In my baseline tally, Oregon (and its seven votes it holds in the Electoral College) was placed into the “Mostly”-Democratic category. This was due to its history in past American presidential elections. In the last seven elections (since 1988), the citizens of Oregon have voted for the nominee of the Democratic Party all seven times. In the past three elections (2004, 2008, 2012), the nominee from the Democratic Party has actually won a majority (over 50%) of the votes. The median margin of victory for the Democratic candidate over the past four elections (since 2000) has been 8.18%. All those figures were not enough to make Oregon a “Solid” state, but its history has shown that it definitely swings blue when it comes to presidential elections.
So, it was with some degree of surprise when the second survey to be released in 2016 that documented the presidential preferences of the citizens of Oregon showed Trump defeating Clinton by 2 percentage points. From May 10-13, Clout Research interviewed 657 likely voters (margin of error 3.8 percentage points, memo here) and Donald Trump was the preferred presidential choice of 292 (44.4%) of the respondents, Hillary Clinton was chosen by 278 (42.3%) of those interviewed, and 88 (13.3%) were unsure.
While Trump’s win in the Clout poll was not decisive because, with the margin of error, the results could also show Clinton at 46.1% (42.3% + 3.8) and Trump at 40.6% (44.4% – 3.8), it is still noteworthy that in a state that has voted Democratic in the past seven American presidential elections would give the Republican candidate a lead of two percentage points.
This result from Clout was all the more surprising because the first survey released in 2016 that documented the presidential preferences of the citizens of Oregon showed Clinton defeating Trump by 11 percentage points. From May 6-9, Davis, Hibbits, & Midghall (DHM) Research (for Oregon Public Broadcasting and FOX 12) interviewed 902 likely voters (margin of error 3.3 percentage points, results here) and Hillary Clinton was the preferred presidential candidate of 385 (43%) of the respondents, Donald Trump was chosen by 288 (32%) of those interviewed, and 228 (25%) selected another option (11% chose “some other candidate”, 11% chose “don’t know”, and 4% chose “will skip this contest”).
Even with the margin of error of 3.3 percentage points, Clinton’s victory in the DHM survey is decisive because her lowest possible percentage of the vote is 39.7% (43% – 3.3) while Trump’s highest figure is 35.3% (32% + 3.3).
So what happened between May 9 (the end of the DHM poll) and May 13 (the end of the Clout survey) that swung the presidential preferences of the citizens of Oregon by 13 percentage points towards the Republican Party?
Unless another poll comes out that shows Oregon leaning red, the short answer to my question in the previous paragraph could be “Nothing.” A possible longer answer is, “Because of who asked the question.”
Note that the DHM poll interviewed 902 likely voters, while the Clout poll only spoke to 657 likely voters. The sample size of Clout survey is more than a quarter (27%) less than the DHM sample. Is it possible that if Clout asked 245 more people (to get level with DHM), all those folks would have cast their ballot for Clinton? Why not? In both the Clout and DHM surveys, Trump wins the nearly the same number of votes (292 with Clout, 288 with DHM) while Clinton’s number of supporters are quite different (278 with Clout, 385 with DHM). Clinton’s number of voters increased by 38% (278 versus 385 ) simply when 37% more voters were asked (657 versus 902).
Sadly, the Clout survey does not provide any detailed breakdown on which demographics voted for which candidate (as opposed to the folks at DHM), but the writers of the Clout report do cite two factors in Trump’s lead and Clinton’s loss. They write “…Trump has a massive lead among Oregon independent voters, winning 53% support compared to just 26% support among independents for Clinton.” They also comment on “her underperformance among women, where she leads Trump by only 9%, far below her national performance among women. Among men, Trump leads Clinton by 13.”
How do those two factors stack up against the only other poll run in Oregon, the poll done by DHM? According to the tables provided by DHM, Clinton’s share of the female vote is 49% compared to Trump’s 27%, a margin of 22 percentage points and well above Clout’s finding of “9%”. As for the male vote, DHM shows that Trump only beats Clinton by a single percentage point (37% versus 36%). Again, a far different number from Clout’s “13”. Again, this difference could be due to the number of likely voters asked. Since there is no breakdown of Clout’s numbers, I can’t tell.
As for the Independent voter, DHM’s survey shows a 32%-29% split with the advantage going to Clinton. The Democratic Party presidential candidate leading among Independents by 3 percentage points (as shown by DHM) is a far different narrative than the numbers given by Clout where Independents lean towards Trump by 27 percentage points. Again, this difference could be chalked up to the difference in the number of people asked in each survey. The difference could also mean that Independent voters are actually turning towards the candidate of the Republican Party.
Or the difference could be because who was asking the questions.
Over at the fivethirtyeight.com website run by Nate Silver, they have a page devoted to rating polling organizations. On that page (found here), Clout Research/Wenzel Strategies (as of this date’s writing) has a Mean-Reverted Bias of “R +1.7”. Silver’s website has this definition for Mean-Reverted Bias:
A pollster’s historical average statistical bias toward Democratic or Republican candidates, reverted to a mean of zero based on the number of polls in the database.
In other words, the results of Clout’s polls, on average, show a bias towards the Republican Party. This figure of “R+1.7” ranks Clout in a tie for seventh place (out of a total of 373 polling firms tracked by fivethirtyeight.com) in terms of a bias towards the GOP. Nate Silver’s website also grades polling organizations and Clout receives a mark (again, as of this date’s writing) of “C-“.
For comparison, DHM (Davis, Hibbits, & Midghall, Inc.) is also tracked by fivethirtyeight.com. The receive a grade of a “B” and their Mean-Reverted Bias clocks in at “R+0.0”, which means there is no bias towards either party.
Was there bias by the polling organizations? Is there an upsurge in Independent voters swinging towards Trump? Are females fleeing Clinton? Was the one-off the Clout survey or the DHM poll?
As I’ve said before, don’t just look at one poll. We will need more surveys from Oregon to answer those and many more questions to see the trends that will help us decide which way Oregon leans.