By Jim Ellis
Aug. 30, 2017 — Two new Nevada Republican polls were released Tuesday that differ so greatly it is difficult to confirm which, if either, is accurate.
JMC Analytics and Polling publicized their new Silver State data (Aug. 24-25; 700 likely GOP registered voters responding to an automated survey) that posts challenger and frequent candidate Danny Tarkanian to be running ahead of incumbent GOP Sen. Dean Heller, 39-31 percent, as the two prepare for a competitive 2018 Republican primary battle.
The Heller campaign immediately responded by releasing their Tarrance Group data from earlier in the month (Aug. 14-16; 300 likely Republican primary voters) that finds a completely different result. According to the Tarrance survey, Sen. Heller actually enjoys a comfortable lead over Tarkanian, 55-33 percent.
So, what does this tell us? In looking at both polling methodologies, we can see certain flaws. The JMC poll is automated with the caveat that the sampling group does not necessarily come from the Nevada universe of actual registered Republican voters. Rather, they could be from a larger segment where the respondents to an automated telephone survey are either self-identified Republicans or from geographic areas where GOP candidates normally perform strongly. Notice that the methodology statement language refers to the sample as being comprised of “likely Republican registered voters”, as opposed to the normal “likely Republican (or Democratic) primary voters.”