McCain urges colleagues to reject CIA director nominee Gina Haspel McCain's closest ally, Sen. Lindsey Graham, says he will vote "yes" on Haspel.

Arizona Republican Sen. John McCain is calling on his Senate colleagues to reject President Donald Trump’s nominee to lead the CIA, Gina Haspel, saying her refusal to acknowledge “torture’s immorality” is disqualifying.

In a statement, McCain said he believes Haspel is a “patriot who loves our country and has devoted her professional life to its service and defense.”

“However,” McCain continued, “Ms. Haspel’s role in overseeing the use of torture by Americans is disturbing. Her refusal to acknowledge torture’s immorality is disqualifying.”

He added: “I believe the Senate should exercise its duty of advice and consent and reject this nomination.”

The powerful chairman of the Senate Armed Services Committee was held in captivity as a prisoner of war for five years in then-North Vietnam, and was tortured. He remains at his home in Arizona as he battles brain cancer, and is not expected to be in Washington for Haspel’s confirmation vote.

During a heated exchange with California Democrat Sen. Kamala Harris, Haspel declined to answer "yes" or "no" when the senator asked whether the use of interrogation tactics – that critics say amount to torture – was immoral.

"Please answer yes or no. Do you believe, in hindsight, that those techniques were immoral?" Harris asked of the nominee.

Haspel responded: "Senator, what I believe sitting here today is that I support the higher moral standard we have decided to hold ourselves..." before Harris cut her off, again pressing her to answer the question.

"I think I've answered the question," Haspel replied.

"No you've not. Do you believe the previous techniques now armed with hindsight, do you believe they were immoral yes or no?" Harris asked.

"Senator, I believe that we should hold ourselves to the moral standard outlined in the army field manual," Haspel replied, not directly answering Harris' question.

Later on in the hearing, Haspel affirmed that should she be confirmed, she will not bring back the agency's controversial rendition, detainee, and interrogation program.

“I can offer you my personal commitment clearly, and without reservation, that under my leadership, on my watch, CIA will not restart a detention and interrogation program. CIA has learned some tough lessons from that experience," Haspel said during the confirmation hearing before the Senate Select Committee on Intelligence.

"We were asked to tackle a mission that fell outside our expertise. For me, there is no better example of implementing lessons learned than what CIA took away from that program,” she said.

Under tough questioning from ranking Democrat Sen. Mark Warner, Haspel reiterated the promise: “I would never ever take CIA back to an interrogation program.”

Despite McCain's firm rebuke of Haspel, it was not enough to sway his closest ally in the Senate.

"I intend to support Gina Haspel to serve as the first female Director of the CIA," Sen. Lindsey Graham, R-S.C., said in a statement Thursday morning. "Ms. Haspel has rejected the interrogation policies of the past. She is fully committed to following the law that prevents future abuses. This law, among others, includes the Detainee Treatment Act which I helped author. Gina Haspel should be confirmed as soon as possible as we live in a time of continuing threats."

Haspel is expected to be confirmed by the Senate later this month. So far, GOP Sen. Rand Paul of Kentucky is the only other Republican to announce he will not support her confirmation.

And she will have the support of at least one Democrat: Sen. Joe Manchin of West Virginia, who announced on Wednesday he will support her as the next CIA director.

ABC News' Luis Martinez contributed to this report.