The outreach may not expand the president’s meager support among African-Americans, but it appeared aimed at reassuring suburban white voters discomfited by his use of racist tropes and incendiary language. Mr. Trump has played to the nation’s raw racial divide as no other president has in the modern era, repeatedly stoking public feuds with African-American athletes and lawmakers while describing Latin American migrants as marauding invaders and rapists.

Over the summer, he demanded that four liberal Democratic congresswomen of color “go back” to their home countries, even though three were actually born in the United States and the other was a naturalized citizen. He went after Representative Elijah E. Cummings, Democrat of Maryland, describing his Baltimore district as a “disgusting, rat and rodent infested mess” where “no human being would want to live.” Mr. Cummings died last month from a long illness…

It did not go unnoticed on social media that at least a couple of the people wearing “Blacks for Trump” were actually white. The president asked the crowd whether they preferred “Blacks for Trump” or “African-Americans for Trump” and they began chanting, “Blacks for Trump! Blacks for Trump!”