Nope- still going up! Nope- still going up!It takes more than voters who identify as Republican to win the White House, so look to national polls that are more than just registered voters who identify as Republican.
BTW, Trump has negatives that are at Hillary levels. With that in mind...
... If I am not mistaken, Romney was at 51% negative in national polls but that was after he had secured the nomination and went through the GOP primaries - not before them.