Here's a quick post on a graph I was curious about, namely the presidential polls vs the markets. I did a similar exercise for the Brexit vote by tracking a moving average of averages of the polls (aka poll of polls) which ultimately gave the right lead on the outcome and showed some relation to the Eurostoxx. So I think it's only appropriate that I do the same for the US presidential election.
It's fair to say there doesn't look to be much if any relationship between the poll spread and the S&P500 at this point as the lead swings around in what still appears to be a reasonably close race. For the Brexit event, it was somewhat similar although there was more consensus around the (negative) impact of a Brexit outcome. In the case of the presidential election outcome, the impact is more ambiguous and the uncertainty around that is probably already reflected to some extent in policy uncertainty. It's also worth noting that in the case of the Brexit event the ultimate outcome lead to a major market shock, rather than a mild meandering market relationship.
As for the poll of polls, here's how the charts are tracking (data courtesy of RealClearPolitics):
Disclosure: I have no position in the US election, I am not a US citizen, the above analysis is intended to be apolitical and instead attempt to draw out macro/market insights rather than make any political statement.