That's what Joan Walsh at Salon.com thinks.
Donald Trump’s remarkable Thursday press conference, where he floridly swore a pledge of allegiance to the GOP – "and to the conservative principles for which it stands" – marks a crossroads for the party. Trump didn’t declare his fealty to Republicans; he exacted their fealty to him. It’s Donald Trump’s party now, and good luck getting anything but white votes anytime soon.
Why that last prediction? Here is another observation from Heather Digby Parton also at Salon.
... The focus of American right wing populism is generally aimed downward at immigrants and poor people, not upward at the wealthy. The Republican base may have an abstract beef with "bail-outs" for the rich but they are utterly convinced that the government’s primary mission is to take their hard earned money and give it to lazy undeserving people who refuse to work.
This last bit underscores the GOP disdain for immigrants and poor as the instantiation of Ayn Rand's characterization of the poor (in Alas Shrugged) as "moochers", "looters", and "unthinking brutes."