YouGov - National: Clinton +5

[Mr. Morden]

Trump is at 1% support among blacks…tied for 3rd place with Johnson:
Clinton 86%
Stein 2%
Johnson 1%
Trump 1%

Other demos…

Dems
Clinton 91%
Trump 4%
Johnson 1%
Stein 0%

GOP
Trump 82%
Clinton 7%
Johnson 3%
Stein 1%

Indies
Trump 45%
Clinton 31%
Johnson 8%
Stein 4%

men: Trump +4
women: Clinton +12
under 30: Clinton +25
30-44: Clinton +20
45-64: Clinton +4
65+: Trump +22
whites: Trump +15
blacks: Clinton +84 (over Stein)
Hispanics: Clinton +49
under $50k: Clinton +2
$50-100k: tie
over $100k: Clinton +22

So yeah, oddly enough, they have Clinton basically tied with Trump among voters making less than $100k, but with a 20 point lead among those making over $100k.  The over $100k subsample is ~200 people.

fav/unfav %:
Clinton 41/58% for -17%
Trump 38/61% for -23%

[Mr. Morden]

Clinton 46 (+4)
Trump 41 (+3)

Core supporters of both parties 'coming home'?

The thing is, even in most of the recent polls that have Trump still somewhat competitive, his gains seem to be mostly coming from self-described Independents rather than Republicans.  Trump is still getting not much more than 80% of Republicans.  In this poll, for example, this is how much support Clinton and Trump gained/lost among the different party crosstabs compared to the previous poll:

Dems
Clinton +8
Trump -3

GOP
Clinton +4
Trump +1

Indies
Clinton -1
Trump +8

So both Clinton and Trump are gaining at the expense of 3rd parties/undecided, but Clinton's new support comes more from Dems, while Trump's new support comes from Indies (though I'm assuming those are self-described Indies who normally vote GOP).  In this poll at least, Clinton is actually gaining more ground with Republicans than Trump is.

[Mr. Morden]

More crosstabs…

People who voted in the Dem. primaries:
Clinton 85%
Trump 6%
Stein 3%
Johnson 1%

People who voted in the GOP primaries:
Trump 78%
Clinton 11%
Johnson 4%
Stein 0%

People who supported Sanders in the primaries:
Clinton 71%
Trump 9%
Stein 7%
Johnson 3%

People who supported a Republican candidate other than Trump in the primaries:
Trump 65%
Clinton 17%
Johnson 9%
Stein 0%

Also, 98% of Clinton supporters from the primaries still support her in the GE, with the other 2% undecided.  94% of Trump supporters from the primaries still support him in the GE, with the other 6% supporting other candidates or undecided.