Pretty straightforward article on WashPo today about the enormous hurdle facing Trump (or another other GOP nominee). The Electoral College is not kind of Republicans right now, and there's no reason to think that changes now.
Long and short of it, Dems have 242 fairly safe electoral votes. All the need is Florida to win. Or various combination of Ohio, Colorado, Nevada, Arizona, New Mexico, Virginia, and North Carolina. There's almost no wiggle room on the Republican side, they need to win nearly all those states.
This isn't even accounting for Trump's favorability ratings.
Trump's been talking about a "landslide", but barring some sort of external act like Clinton getting indicted, it's hard to see a way they even win, much less by a big margin.