The party may eventually split as they continue moving right while failing to capture voters from the GOP, with some switching sides to avoid backlash, but probably not while they monopolize center-left organizing and fundraising and as long as rank and file Democratic voters blindly prop them up, lured by false promises and fear of Trump. It's also unclear if a third party can compete well enough to replace them under those conditions.
But the tiger isn't going to change his stripes.