Results of a new poll carried out by The Simon Poll/SIUThe Simon Poll/SIU were spread on October 12. The poll asked interviewees from Illinois for whom they will vote: Donald·Trump or Hillary·Clinton.
The Simon Poll/SIUThe Simon Poll/SIU poll results
Of those who responded, 53.0% said that they are going to vote for former First Lady Hillary Clinton, while 28.0% said that they would give their vote to real estate developer Donald Trump.
The poll was carried out from September 27 to October 2 among 865 likely voters. Considering the poll's margin of error of +/-3.3 percentage points, the difference between both candidates is statistically significant.
Putting the results in context
Individual polls should be treated with caution, as they may incorporate substantial errors. Rather than relying on results from single polls, the best practice scientific advice is to rely on combined polls or, even better, a combined forecast that includes forecasts from different methods, each of which draws upon different data.
For the following analysis, we convert Clinton's and Trump's raw poll numbers into two-party vote shares. This yields figures of 65.4% for Clinton and 34.6% for Trump.
Comparison to other polls
Clinton can currently count on 59.2% of the major two-party vote in an average of recent polls in Illinois. This value is 6.2 percentage points lower than her corresponding numbers in the The Simon Poll/SIUThe Simon Poll/SIU poll. This difference is outside the poll's error margin, which suggests that the poll is an outlier.
Results compared to the combined PollyVote forecast
The most recent PollyVote forecasts Clinton to gain 59.0% of the two-party vote in Illinois. Hence, the PollyVote forecast is 6.4 points below her polling numbers. The PollyVote forecast is thus outside the poll's sampling error.