Maggie Haberman and Jonathan Swan

Eight years after helping Donald J. Trump get elected — and four years after being released from prison — the longtime political operative was back as a volunteer to advise the G.O.P. convention.

Todd Blanche upended his career to represent Donald J. Trump and has been the former president’s favorite. But Mr. Trump has made him a focus of his episodic wrath.

It is not clear what the former president discussed with Prince Mohammed bin Salman, but news of their call came amid Biden administration negotiations with the Saudis over a Middle East peace plan.