WTHR/Howey Politics released the results of a new poll, in which respondents from Indiana were asked for whom they will vote: Republican Donald Trump or Democrat Hillary Clinton.
WTHR/Howey Politics poll results
Of those who answered the question, 36.0% said that they would vote for former Secretary of State Hillary Clinton, while 43.0% declared that they would give their vote to billionaire Donald Trump.
The poll was conducted from September 6 to September 8 among 600 likely voters. There is a sampling error of +/-4.0 percentage points. Considering this error margin, the gap between both candidates 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, as they often incorporate large errors. Rather than relying on results from single polls, one should look at combined polls or, even better, a combined forecast that includes forecasts from different methods, each of which includes different data.
For the following comparison, we convert the candidates' raw poll numbers into two-party vote shares. The corresponding figures are 45.6% for Clinton and 54.4% for Trump. To compare: Only 45.4% was obtained by Clinton in the WTHR/Howey Politics poll on April 21, for Trump this result was 54.7%.
Results vs. other polls
If we look at an average of Indiana polls, Trump's two-party vote share is currently at 55.5%. This value is 1.1 percentage points higher than his respective numbers in the WTHR/Howey Politics poll. This difference is within the poll's error margin, which suggests that the poll is not an outlier.
Results compared to the combined PollyVote prediction
The most recent PollyVote foresees Trump to gain 56.9% of the two-party vote in Indiana. Hence, Polly's prediction is 2.5 points above his polling numbers. Again, a look at the poll's sampling error shows that this difference is negligible.