Is that promoting Trump or dooming him? The question points to one of the central riddles of his candidacy. Without his megawatt profile, it’s hard to imagine a figure with no previous political experience rolling over arguably the most talented Republican field in modern history — and with a platform, no less, that gores decades of conservative orthodoxy. But for all the evident appeal of that populist message, at least to a plurality of Republican primary voters, it’s overshadowed too often by distractions from Trump’s sky-scraping ego. The simple solution — the one dozens of vulnerable Congressional Republicans are rooting for, that Trump rise to the moment and start behaving, as he’s said, “presidential” — assumes too much about either real human changeability or the candidate’s demonstrably lacking acting chops. In other words, no matter what he calls himself, for better or worse, Trump’s gonna be Trump.

That combustible mix of messenger and message now turns to confront an unsettled general election audience. We wrote in this space last week that Trump faces an uphill climb in the fall contest barring an economic cataclysm, given his historically high unpopularity among key voting groups and a jobless rate that keeps inching down while wages begin inching up. As a counterpoint, consider the study out this week from the Pew Research Center that found so far this century, the middle class is shrinking in nearly 90 percent of American cities, home to about three-quarters of the population. The decline has been most acute in communities with an outsize reliance on manufacturing. And they’re mostly in the Rust Belt, where Trump hopes to remake a Democratic-friendly map with his protectionist pitch. It will be competing with the pitchman’s irrepressible habit of stepping on his own lines.