"I thought about the Ramsey Rapist every night before I went to bed for five years," the former FBI director said.
Republican awards honoring conservative African Americans were absent the party's first black chairman.
The Republicans who stick by Trump are hastening their own disaster.
The outsider may have the establishment worried.
Aides to the candidates want control of the debates. Will the Republican National Committee be able to stay in the driver's seat?
Infighting over the debate process has split candidates, national committee.
Republican candidates are seeking control over how the debates are run.
The pledge is widely viewed as an effort to convince Trump not to run as a third-party candidate, a move which could strip away potential GOP voters.