Alexander Burns' article at Politico is linked below.
Alexander Burns: The Decline of GOP Mayors in Major Cities
"Largely unnoticed in Washington, urban Republican politicians have emerged over the last year as perhaps the nation’s most severely endangered political species, as the party has either failed to compete for high-profile mayor’s offices or has been soundly rebuffed by voters. It’s a significant setback that some Republicans view as an ominous sign for the GOP in a country growing steadily more urban and diverse."
---Alexander Burns, Politico