Dan O'Donnell of the Dan O'Donnell Show first reported on this "major" ad buy, which he said signals the Trump campaign's big push for black voters in the battleground state of Pennsylvania.

"This follows my exclusive report several weeks ago that the Harris campaign was moving radio money out of Milwaukee and aggressively buying ads on those same two Philadelphia stations to shore up her black support," he said, and also that the Republican Party of Wisconsin is "making a significant urban radio buy in Milwaukee."

"Taken together, the spending indicates that Harris is deeply concerned about black turnout in Philadelphia and Trump sees this weakness and is aggressively going after voters there and in Milwaukee," he concluded.

Indeed, the Harris campaign has been worried not just about Pennsylvania but also support from black voters across the country. Former President Barack Obama sounded the alarm on October 10, telling Harris supporters in — yes, Pennsylvania — that they have "not yet seen the same kinds of energy and turnout in all quarters of our neighborhoods and communities, as we saw when I was running."

"Now, I also want to say that seems to be more pronounced with the brothers," Obama continued, lecturing black men.

"So if you don't mind, just for a second, I'm going to speak to y'all, and say that when you have a choice that is this clear, when on the one hand, you have somebody who grew up like you, knows you, went to college with you, understands the struggles and pain and joy that comes from those experiences," he added.