I’m not a communist, Hitler. (See how dull and pointless it gets instantly?).  

More precise and useful would be something like, Kamala Harris is a Bay Area Progressive of mixed immigrant ancestry, and the first woman of color to be nominated for president by a major party.

Donald Trump is a former Democrat who tapped into a latent populist impulse among disaffected white voters, transforming the GOP into an unrecognizable, isolationist and xenophobic form in 8 years.  

Each reflects the collapse of centrist elements in the American partisan duopoly, and each draws 50% of likely voters.

Or we can call each other inaccurate names.