NBC-WSJ-Marist published the results of a new poll. In this poll, participants from Pennsylvania were asked for whom they will vote: Donald Trump or Hillary Clinton.
NBC-WSJ-Marist poll results
According to the results, 48.0% of interviewees plan to cast a ballot for former First Lady Hillary Clinton, whereas 37.0% are going to vote for billionaire Donald Trump.
The poll was carried out from August 3 to August 7 with 834 registered voters. There is a sampling error of +/-3.4 percentage points. Considering this error margin, the race is currently a statistical tie.
Putting the results in context
Single polls can include large biases, and should be interpreted with caution. At least, one should examine how a poll's results compare to benchmark forecasts.
For the following analysis, we convert Clinton's and Trump's raw poll numbers into shares of the two-party vote. The respective figures are 43.5% for Clinton and 0.0% for Trump.
Results in comparison to other polls
Looking at an average of Pennsylvania polls, Clinton's two-party vote share is currently at 44.8%. This value is 1.3 percentage points higher than corresponding numbers in the NBC-WSJ-Marist poll. This margin is within the poll's error margin, which means that the poll is not an outlier.
Results compared to the combined PollyVote forecast
The most recent PollyVote foresees Clinton to gain 45.5% of the two-party vote in Pennsylvania. Hence, the combined PollyVote is 2.0 points above polling numbers. Again, a look at the poll's margin of error reveals that this deviation is negligible.