It's still Trump's nomination to win or lose, but nothing is set in stone, there is nothing inevitable.
Fwiw, I've noticed Trump going after the bamster and the shrill one a lot lately, a sign he's consolidating and thinking the long view. IMHO it will be a done deal in about three months.
To me, this is how you win the primary...I know the conventional wisdom is not this, but conventional DC wisdom is almost always WRONG. Remember Newt in 2012? When he was kicking butt, he was kicking liberal butt not Republican butt.