Olsen finds the small city/town/rural GOP bias got stronger while the big city/suburb Dem bias was about the same. From this he concludes:
Trump will again be competitive in the Midwestern purple states of Ohio, Michigan, Iowa, and Wisconsin, and perhaps even Pennsylvania where two weak candidates this cycle depressed GOP vote share. Should Trump be able to improve only a small amount on his party’s 2018 results in these states, he will again prevail in the Electoral College even as he again loses the popular vote.An incumbent president can normally improve that small amount on his party’s midterm results. Not the landslide we’d prefer, one supposes, but a win is a win. Hat tip to RealClearPolitics for the link.