“I would rather have any leadership PAC support the person they were formed to support, not by running down others,” Hatch told The Hill. “I would not do that. I’d tell them to do things that support Jeb.”

Sen. Pat Roberts (R-Kan.), who is neutral in the presidential primary, also called for Bush allies to hold their fire.

“I agree with Orrin,” he said. “I don’t think it’s working for Jeb. I certainly don’t think it’s working for the best course of action that [Speaker] Paul Ryan [R-Wis.] talked about for the party to be successful.

Republicans like Roberts and Hatch increasingly see Rubio as their party’s best candidate for winning back the White House.