Results of a new poll conducted by Detroit NewsDetroit News were distributed on October 12. The poll asked respondents from Michigan for whom they will vote: Donald·Trump or Hillary·Clinton.
Detroit NewsDetroit News poll results
Of those who answered the question, 47.0% said that they plan to vote for former New York Senator Hillary Clinton, while 33.0% revealed that they would give their vote to businessman Donald Trump.
The poll was conducted from October 10 to October 11 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, one should not have too much faith in the results of single polls, because they sometimes incorporate large errors. Instead of relying on results from single polls, forecasting research recommends to consult combined polls or, even better, the combined PollyVote forecast that incorporates forecasts from different methods, each of which draws upon different data.
For the following analysis, we translate the candidates' raw poll numbers into shares of the two-party vote. This yields figures of 58.8% for Clinton and 41.3% for Trump. In the most recent Detroit NewsDetroit News poll on September 28 Clinton obtained only 54.1%, while Trump obtained 45.9%.
Comparison to other polls
An average of recent polls in Michigan has Clinton at 57.0% of the two-party vote. Relative to her numbers in the Detroit NewsDetroit News poll Clinton's poll average is 1.8 percentage points worse. This difference is within the poll's margin of error, which suggests that the poll is not an outlier.
The poll compared with PollyVote's forecast
The current PollyVote predicts Clinton to gain 54.6% of the two-party vote in Michigan. That is, Polly's prediction is 4.2 points below her polling numbers. Again, a look at the poll's sampling error reveals that this difference is significant.