Some of the subgroups have huge daily jumps. The African American group caught my eye the first time it jumped up (and right back down exactly 7 days later).
I think the poll is manipulated by the pollster, and easy to manipulate.
Agree. It is likely collusion with other pollsters (and possibly Clinton campaign) to cook their numbers as others here have suggested. They are trying, like other MSM polls to depress turnout of Trump supporters.