Last I saw in 2014 was D+7 in Michigan, so the sample is slightly optimistic for Trump, but not too far off.
Right. Keep in mind that party affiliation is likely to be less relevant in this election than it has been in decades. Hillary Clinton is going to get a lot of votes from Republicans (mainly dimwitted women and limp-wristed men), and Trump is going to get a lot of votes — probably more than he loses among Republicans — from Democrats (mainly working-class men of all races).