CHARLOTTE, N.C. — For two days, the president toyed with a bipartisan message and watched as the news cycle focused not on him, and not on the midterm elections, but on at least 14 explosive devices delivered to prominent Democratic figures.

By Friday, he had had enough.

As he left Washington for his latest campaign rally here, President Trump made it clear that he was no longer going to sit through another news cycle without President Trump at the center.

“The Republicans had tremendous momentum, and then, of course, this happened, where all that you people talked about was that,” Mr. Trump said to reporters about the bomb scares. “But now we have to start the momentum again.”

His supporters in North Carolina appeared to agree. When Mr. Trump took the stage at the Bojangles’ Coliseum, hours after Cesar Sayoc Jr., a Florida man with a lengthy criminal record, was arrested in connection to sending the devices, chants of “Build the wall” and “CNN sucks” had already rung out repeatedly.