This new CBS News / YouGov Poll is not a national poll. It was taken between October 12th and 14th of a random sample of 3,260 likely voters in 13 battleground states -- Arizona, Colorado, Florida, Georgia, Iowa, Michigan, North Carolina, New Hampshire, Nevada, Ohio, Pennsylvania, Virginia, and Wisconsin. The poll has a margin of error of 2.5 points.
These battleground states have Hillary Clinton leading Donald Trump by 6 points (46% to 40%). One thing I notice is that Gary Johnson and Jill Stein, of the Libertarian and Green parties respectively, are not doing too well in these states. Overall, Stein has about 2%, while Johnson has about 6% support. If third party voting was going to have an effect on this election, it is in these 13 states where that would happen. But it looks like they will not be a factor.
This election is going to be between those who support Trump (no matter what he does or says) and those who think Trump would make a disastrous president (and will be voting for Clinton). I believe (and fervently hope) that the latter will make up a significant majority of voters.