Des Moines RegisterDes Moines Register published the results of a new poll on October 9. In this poll, participants from Iowa were asked for whom they will vote: Democrat Hillary Clinton or Republican Donald Trump.
Historically, Iowa has been a purple state, in which neither the Republican Party nor the Democratic Party has had overwhelming support to secure that state's electoral college votes. This is why predictions here are of particular importance.
Des Moines RegisterDes Moines Register poll results
Of those who replied, 39.0% said that they will vote for former First Lady Hillary Clinton, while 43.0% indicated that they would give their vote to businessman Donald Trump.
The poll was conducted from October 3 to October 6. A total of 642 likely voters responded. If one takes into account the poll's margin of error of +/-3.9 percentage points, the results reflect a statistical tie.
Putting the results in context
As any other method, polls are subject to bias. As a result, you should not put too much trust in the results of a single poll. Instead of trusting the results from single polls, the recommended strategy rely on combined polls or, even better, the combined PollyVote forecast that uses forecasts from different methods, each of which draws upon different data.
For the following comparison, we convert Trump's and Clinton's raw poll numbers into two-party vote shares. This procedure yields values of 47.6% for Clinton and 52.4% for Trump.
Comparison to other polls
Looking at an average of Iowa polls, Trump's current two-party vote share is at 51.9%. This value is 0.5 percentage points lower than her corresponding numbers in the Des Moines RegisterDes Moines Register 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 most recent PollyVote expects Trump to gain 49.5% of the two-party vote in Iowa. This means that Polly's forecast is 2.9 points below her polling numbers. Again, a look at the poll's sampling error shows that this difference is negligible.