One-party rule has wreaked havoc in the state, and voters might turn to a new crop of Republicans. A visit to the semiannual meetings of the national committees of the two major parties makes you realize that even in the polarizing Age of Trump, a midterm election isn’t one national election but 50 state ones. At last month’s Republican National Committee meeting in Austin, Texas, the mood ranged from optimistic to ready to ready for a funeral On the one hand there was Maryland, where despite the fact that Donald Trump won only 34 percent in 2016, GOP governor Larry...