Slate has run with a thought experiment that serves as a kind of counter to calls by people like President Obama for Republicans to repudiate their own nominee, for the good of the country.  The idea here is that if populist Democrats had somehow handed the nomination to somebody like Sean Penn, people left of center would not take kindly to being told to vote for Ted Cruz in the name of apple pie and American values.

To me the analogy is flawed because Ted Cruz is easily as unreasonable a choice for President as Donald Trump is, and Cruz came in second which means that the Republican primaries went from 20 people down to two who are totally unfit for the White House.  On the Twitter, Ross Douthat suggested Rick Santorum as the Republican thought experiment candidate but, again, is Santorum any more acceptable than Trump?  Maybe John Kasich should be the guy or even Mitt Romney. People who don't want those two to be President at least don't believe that the idea of a President Kasich or President Romney is somehow an existential threat to democracy.  Would you vote for one of them if the alternative would be to keep Sean Penn out of office?

At that point, I'd probably duck the question and vote for a third party candidate, but if you take that off the table it does become an interesting question.  I'd say it really depends on who the Republican nominee is. Put another way, yes, I'd vote for Penn over a far right Republican nominee, particularly if that nominee is a religious conservative or seems racist, but I'd vote for a moderate Republican over Penn, I guess I could say that much.

So the funny thing from the left point of view is that we've nominated a moderate and Trump isn't event a good conservative, so what's the problem?  Well, the problem is that Republicans don't consider Clinton a moderate. They never considered Obama a moderate either.  They think we're all Sean Penn.  That's the problem.