Results of a new poll conducted by Roanoke College were announced. The poll asked respondents from Virginia for whom they will vote: Republican Donald Trump or Democrat Hillary Clinton.
Virginia is traditionally a battleground state, where Democrats and Republicans have often won similar levels of voter support. Hence, the election outcome in that state is considered important in determining the overall result of the presidential election.
Roanoke College poll results
Of those who replied, 51.0% said that they will vote for former New York Senator Hillary Clinton, while 38.0% revealed that they would give their vote to billionaire Donald Trump.
The poll was conducted from October 2 to October 6. A total of 814 likely voters responded. If one accounts for the poll's sampling error of +/-3.4 percentage points, the difference in voter support is statistically significant.
Putting the results in context
As any other method, polls are subject to bias. Hence, you should not be too confident the results of an individual poll. Rather than relying on results from single polls, you should look at combined polls or, even better, a combined forecast that uses forecasts from different methods, each of which draws upon different data.
For the following analysis, we convert the candidates' raw poll numbers into two-party vote shares. The corresponding figures are 57.3% for Clinton and 42.7% for Trump. In the latest Roanoke College poll on January 26 Clinton received 59.8%, while Trump received only 40.2%.
Results vs. other polls
Looking at an average of Virginia polls, Clinton's two-party vote share is currently at 55.6%. This value is 1.7 percentage points lower than her respective numbers in the Roanoke College poll. This margin is within the poll's sampling error, which means that the poll is not an outlier.
Results compared to the combined PollyVote prediction
The latest PollyVote forecasts Clinton to gain 52.4% of the two-party vote in Virginia. Hence, Polly's forecast is 4.9 points below her polling numbers. The PollyVote forecast is therefore outside the poll's margin of error.