On October 10, NBC-WSJ-Marist released the results of a new poll, in which respondents from Pennsylvania were asked for whom they will vote: Republican nominee Donald Trump or Democrat nominee Hillary Clinton.
NBC-WSJ-Marist poll results
Of those who replied, 51.0% said that they will vote for former Secretary of State Hillary Clinton, while 39.0% revealed that they would give their vote to businessman Donald Trump.
The poll was conducted from October 3 to October 6 with 709 likely voters. There is a sampling error of +/-3.7 percentage points. Considering this error margin, the gap between both candidates is statistically significant.
Putting the results in context
Individual polls should be interpreted with caution, because they often incorporate large biases. At the very least, one should examine how a poll's results compare to benchmark forecasts.
In order to make the results comparable to benchmark forecasts, one can convert them into shares of the two-party vote. This procedure results in values of 56.7% for Clinton and 43.3% for Trump.
Results in comparison to other polls
Clinton can currently count on 55.3% of the two-party vote according to an average of recent polls in Pennsylvania. Relative to her numbers in the NBC-WSJ-Marist poll Clinton's poll average is 1.4 percentage points worse. This margin is within the poll's margin of error, which suggests that the poll is not an outlier.
The poll in comparison with PollyVote's forecast
The most recent PollyVote foresees Clinton to gain 53.0% of the two-party vote in Pennsylvania. Hence, Polly's prediction is 3.7 points below her polling numbers. The PollyVote forecast is thus in line with the poll's margin of error.