It's what has happened in Ohio that is the big reversal. Clinton has a 60% chance of winning...when Donald had been given the edge a week ago. I think the did not pay taxes story has hurt him badly with the key Blue Collar voters in Ohio.
Ohio's been given a lot of attention, but it's everywhere. (And whether the polls adjust themselves or not, the worst prognostication is often Ohio. They just don't seem to find a way to poll the inner cities and rely on roving reporters saying, "Gosh, Ed. It just doesn't seem to be a lot of support for the Democrats.")
538 has Iowa turning blue. Once RCP puts the blue states in the gray boxes, Trump has about zero routes to victory. RCP has the most conservative projections at present. A candidate has to be leading by 6 or more for them to change the color. If they move WI, MN, NH, ME to light blue, Hillary's at 272.
And that's without FL or OH or NC, all of which Clinton will probably win.
The real key that the GOP hasn't commented on is that conservative-friendly RCP has had Trump on a solid 165 all along. Big wins for him in polling news consist of "hey, it's closer in New Hampshire than we thought". Usually based on one poll. And poof(!) a week later Hillary's up by four on the average and cruisin'. Meanwhile Donald keeps spending his money in those places and when he leaves town the polls shift to Hillary. PA, MI, NH, CO, NV. Donald's the best campaign tool the Dems have. He cuts a swath through the local Fox interviews, trashes whomever is on his list that day, and four thousand people of all stripes (unions in NV, teachers in NH, never-trumpers in MI) shudder collectively and say, "I gotta call me the Clinton HQ and help stop this schmuck!".
The Trump Challenge:
Find a way to break 200 Electoral Votes. Yeah, it's that grim for him. He's got his ironclad 165. He can go to 192 with AZ and GA, which I think he'll take. He might get six in IA. I don't think he gets any others.... not OH, not FL, not NC.
<--There ain't enough of these.