NBC-WSJ-Marist released the results of a new poll, in which respondents from Ohio were asked for whom they will vote: Democrat candidate Hillary Clinton or Republican candidate Donald Trump.
In Ohio, the election outcome is often close. This is the reason why the state is commonly viewed as a battleground state, which makes it particularly interesting from a forecasting perspective.
NBC-WSJ-Marist poll results
The results show that 43.0% of interviewees plan to vote for former New York Senator Hillary Clinton, while 38.0% plan to vote for businessman Donald Trump.
The poll was conducted from August 3 to August 7 among 889 registered voters. If one takes into account the poll's margin of error of +/-3.3 percentage points, the results reflect a statistical tie.
Putting the results in context
Single polls should be interpreted with caution, as they can contain substantial errors. Instead of relying on results from single polls, research in forecasting recommends to use combined polls or, even better, a combined forecast that uses different methods and data.
For the following comparison, we convert Clinton's and Trump's raw poll numbers into two-party vote shares. This yields figures of 53.1% for Clinton and 46.9% for Trump.
Results in comparison to other polls
Looking at an average of Ohio polls, Clinton's current two-party vote share is at 52.8%. This value is 0.3 percentage points lower than her respective numbers in the NBC-WSJ-Marist poll. This difference is within the poll's error margin, which suggests that the poll is not an outlier.
The poll in comparison with PollyVote's prediction
The latest PollyVote foresees Clinton to gain 52.1% of the two-party vote in Ohio. Hence, the PollyVote is 1.0 point below her polling numbers. The PollyVote forecast is therefore within the poll's error margin.