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 decided by a narrow margin. This is the reason why the state is commonly referred to as a battleground state, which makes it particularly interesting from a forecasting perspective.
NBC-WSJ-Marist poll results
According to the results, former First Lady Hillary Clinton and real estate developer Donald Trump have the same level of support, each with 45.0% of the vote.
The poll was carried out from October 10 to October 12 with 724 likely voters. If one accounts for the poll's error margin of +/-3.6 percentage points, the results reflect a statistical tie.
Putting the results in context
Individual polls should be treated with caution, since they can incorporate large biases. At the very least, one should check how a poll's results compare to benchmark forecasts.
To make the results comparable to forecasts from benchmark methods, one can convert them into two-party vote shares. The results of the actual poll mean 50.0 % for Clinton and 50.0 % for Trump for the two-party vote share. On August 7 Clinton received only 46.9% in the NBC-WSJ-Marist poll and Trump received only 0.0%.
Results compared to the combined PollyVote prediction
The most recent PollyVote predicts Clinton to gain 51.4% and Trump 48.6% of the two-party vote in Ohio. Clinton has 1.4 percentage points less when the results of the poll are compared to the combined PollyVote forecast for Ohio. Again, a look at the poll's error margin shows that this difference is significant.