Results of a new poll carried out by NBC-WSJ-Marist were published. The poll asked respondents from Pennsylvania for whom they will vote: Republican Donald Trump or Democrat Hillary Clinton.
NBC-WSJ-Marist poll results
Of those who replied, 51.0% said that they are going to vote for former First Lady Hillary Clinton, whereas 39.0% declared that they would give their vote to businessman Donald Trump.
The poll was conducted from October 3 to October 6. A total of 709 likely voters responded. If one takes into account the poll's margin of error of +/-3.7 percentage points, the spread between both candidates is statistically significant.
Putting the results in context
Single polls often incorporate large errors, and should be treated with caution. Rather than relying on results from single polls, the best practice is to rely on combined polls or, even better, a combined forecast that uses forecasts from different methods, each of which draws upon different data.
In order to make the results comparable to forecasts from other methods, one can convert them into two-party vote shares. The respective figures are 56.7% for Clinton and 43.3% for Trump. On August 7 Clinton obtained only 43.5% in the NBC-WSJ-Marist poll and Trump obtained only 0.0%.
Results vs. other polls
Clinton can currently count on 55.3% of the two-party vote in an average of recent polls in Pennsylvania. This value is 1.4 percentage points lower than her respective numbers in the NBC-WSJ-Marist poll. This margin is within the poll's margin of error, which means that the poll is not an outlier.
Results compared to the combined PollyVote prediction
The most recent PollyVote foresees Clinton to gain 53.6% of the two-party vote in Pennsylvania. Hence, Polly's prediction is 3.1 points below her polling numbers. Again, a look at the poll's error margin suggests that this deviation is negligible.