From the story here:
After that contest [North Dakota], Brian Baker, a senior adviser to the PAC [Our Principles PAC], issued a statement asserting that the race “is coming down to a ground game battle for delegates. We will fight for every last delegate vote all the way to Cleveland.” Baker also advises the PAC’s biggest donors, the Ricketts family, who had contributed $5 million of the $8 million raised by the PAC through the end of February, and who had come under fire from Trump when their involvement was revealed.
