Is Trump’s Electoral College Advantage a Mirage?

The conventional wisdom going into next Tuesday’s election is that Donald Trump has a built-in advantage in the Electoral College, and that if he can narrow the gap in the popular vote to 2 or 3% or maybe even 4%, he can retain the Presidency.

This expectation results partly from his 2016 victory, as Hillary Clinton had a 2.1% popular vote lead but still lost handily in the…