The GOP got annexed by the billionaire neo-feudalists decades ago. Trump's brazen ripping up the boards to show the cockroaches has only accelerated the inevitable, but (ironically) has also exposed the rot in the system before it was irreversible. The GOP slow toxic death began with Nixon's Southern Strategy.
As many, many, many people (including me) have pointed out, the DNC was merely the last bastion for anyone not ruthless enough to be GOP to enter politics. The annexation of the DNC has also been happening (which is why Trump donated to the Clinton campaigns - business investment), although more slowly. When the GOP finally completes the implosion (leaving the Libertarians to those wealthy enough to claim they don't need anyone else, and the newly reformed and renamed "Fascist" party to those Trump dumps after pillaging them), the billionaire class will move aggressively to reshape the DNC using exactly the same methods they did with the GOP.
Thank God for Sanders to expose that problem with the DNC by providing some contrast. Sanders is only a leaning post left of center, but the contrast and mobilization means evolution and a new, truely Progressive movement might emerge from the humiliating ashes of the 2016 election.