NBC-WSJ-Marist released the results of a new poll, in which respondents from Pennsylvania were asked for whom they will vote: Democrat candidate Hillary Clinton or Republican candidate Donald Trump.
NBC-WSJ-Marist poll results
Of those who responded, 48.0% said that they will vote for former First Lady Hillary Clinton, while 37.0% indicated that they would give their vote to real estate developer Donald Trump.
This poll was conducted from August 3 to August 7, among a random sample of 834 registered voters. Taking into account the poll's error margin of +/-3.4 percentage points, the spread in voter support is statistically significant.
Putting the results in context
As a general rule, however, a good strategy is to not have too much faith in the results of single polls, since they can contain large errors. Rather, one should check how a poll's results compare to benchmark forecasts.
For the following comparison, we translate Trump's and Clinton's raw poll numbers into shares of the two-party vote. The respective figures are 56.5% for Clinton and 43.5% for Trump.
Comparison to other polls
Clinton currently runs at 55.2% of the two-party vote in an average of recent polls in Pennsylvania. This value is 1.3 percentage points lower than her respective numbers in the NBC-WSJ-Marist poll. This margin is within the poll's margin of error, which suggests that the poll is not an outlier.
Results compared to the combined PollyVote prediction
The current PollyVote foresees Clinton to gain 53.3% of the two-party vote in Pennsylvania. That is, Polly's prediction is 3.2 points below her polling numbers. Again, a look at the poll's sampling error shows that this difference is negligible.