Flagging in the polls, U.S. Republican presidential nominee Donald Trump has decided to shake up his campaign, bringing in Stephen Bannon, head of Breitbart News LLC, as CEO. Paul Manafort, the experienced Republican operative who has urged Trump to pivot toward the center for the general election, resigned Friday morning.

Since the GOP convention in July, Trump's poll numbers have plummeted, as he denigrated a Muslim Gold Star mother whose son died in Iraq; insisted that President Barack Obama and Democratic presidential nominee Hillary Clinton were the "founders of ISIS," and suggested that "Second Amendment people" might take care of Clinton if she were elected president. But Trump apparently blames his flagging popularity on Manafort and others pushing him to pivot, lay out policy addresses and appear more "presidential."

"I am who I am," Trump told Wisconsin radio, "It's me. I don't want to change. I don't want to pivot. I mean you have to be you."