The Texas Tribune, working with the University of Texas, released a poll asking Texas voters about their support for candidates in the Democratic primary. The poll found Bernie Sanders leading the race for Texas’ 261 delegates with 24% of the vote, with Joe Biden a close second at 22%. Elizabeth Warren and Michael Bloomberg followed behind the top two with 15% and 10%, respectively. Further down on the list Andrew Yang, Amy Klobuchar, and Pete Buttigieg all had 7% or lower.
It is important to remember that while we think of polls as a snapshot of public opinion, they are often conducted over a period of time. During the polling window, public opinion can change. For example, the UT/TT poll was conducted from January 31st – February 9th, and then released to the public on February 14th. Here is a brief list of “major events” that occurred during the time this poll was in the field: the Iowa Caucuses, the State of the Union, Donald Trump’s impeachment trial acquittal, the New Hampshire Democratic debates, and the release of the president’s proposed budget. Also, on February 11, after the UT/TT poll was conducted, New Hampshire voters went to the voting booths for the first in the nation primary election. Does the UT/TT poll actual provide a snapshot of public opinion on February 14th? Nate Cohn, a polling writer for the NY Times, used a football analogy to describe this poll: “If polling is just a ’snapshot,’ as they say, then [the UT/TT poll is] like taking a blurred minute-long exposure of a potentially decisive play in a football game.” This poll might not provide a clear picture of how each of these events shaped the race through February 14th.
In a previous blog post discussing polling in the week between the Iowa Caucus and the New Hampshire Primary, we discussed a daily tracking poll released by Emerson College that showed the changes in perceptions of the candidates among New Hampshire voters. These polls captured Pete Buttigieg’s post-Iowa surge and part of Amy Klobuchar’s post-debate surge. Topline numbers in a poll conducted over eight days before and after the Iowa caucuses might not have captured the full impact of these individual events. The same issue could apply to the UT/TT poll; if voter preferences changed after these events, it would not be as easy to attribute each event’s impact on the race as it is in the Emerson daily polling. Thus, while the UT/TT poll provides insight into how Texas voters viewed the candidates during this window, it likely did not capture changes in opinions as events unfolded during (and after) the polling window.
Always be sure to check when a poll was conducted. When a poll is released, we are interpreting it through the lens of the present and can easily forget that the respondents were participating in the days, if not weeks beforehand. If a major event occurs while a poll is being conducted (or between then and its release), the results likely will not capture any resulting change in sentiment. This does not make a poll “bad,” as the methodology chosen may have other advantages such as allowing for more responses or capturing some of the dynamic influences of events. In the end, no poll can be timed to give the perfect view on public perception – only the election itself can do that!
And as we saw yesterday, Joe Biden surged in two short days after South Carolina to Super Tuesday victories in Texas and nine other states.
Note: Polling data from the survey can be found here: https://texaspolitics.utexas.edu/set/democratic-presidential-primary-vote-choice-february-2020
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