My response to the author on the first part of that line- No, stop lying, you cannot handle anyone being republican. On the second part of the statement - You cannot stomach anyone voting for any republican.
The amusing thing I have noticed about liberals, in the past few months, is that they are completely astounded when they hear that someone they know voted for Trump.
They can't seem to process the math that someone around them could have voted for Trump.
I have a Ph.D. in Physics!
It's called "cognitive dissonance". Their world-view rests on the datum that anyone who votes Republican is either stupid or evil. If they encounter someone whom they view as neither stupid nor evil, then that shakes up their world a little. Because if a good and intelligent person is conservative, then conservative viewpoints cannot be so easily dismissed.
For some, rather than re-examine their assumptions, they assume that their friend was secretly evil all along, and feel very upset.