Read this poll. It is very telling. (Page 187, or hit the link if you find Trump favorability in the table of contents).
The only positive favorability is in the 65+ age category. Trump is increasing unpopular as you trend downward in age, but only 65+ is a net favorable. Not only is he down in the 45-64 range, he has a -9 net favorability in that group.
His last bastion of popularity is in the 65+ demographic. I maintain that this age demographic has the largest proportion of folks who do not have a full-time job, and can more easily vote than those with full-time jobs. .
Link: Current favorability poll on page 187