Trump's CIA chief confirmation looks secured following two key Democratic votes

Warner, the top Democrat on the Senate intelligence committee, said he was supporting her nomination in what he described as a "difficult decision."

"Over the last year I've had the opportunity to work with Ms. Haspel in her role as Deputy Director, and I have always found her to be professional and forthright with the Intelligence Committee," Warner said. "Most importantly, I believe she is someone who can and will stand up to the President if ordered to do something illegal or immoral -- like a return to torture."

Moments after Warner announced his position, Heitkamp also released a statement backing Haspel.

"After meeting her and talking with former leaders in our intelligence community, I have concluded that Gina Haspel meets these standards. I am therefore planning to vote to confirm her as Director of CIA," Heitkamp said in her statement. "But this was not an easy decision. Ms. Haspel's involvement in torture is deeply troubling, as my friend and colleague, John McCain, so eloquently reminded us. However, Ms. Haspel explained to me that the agency should not have employed such tactics in the past and has assured me that it will not do so in the future."

Warner and Heitkamp are now the third and fourth Democrat to support Haspel's confirmation, while two Republicans have said they will oppose her. With a 51-49 Republican majority -- and one of the GOP no votes, Sen. John McCain, out of Washington battling cancer -- additional Republicans would have to join McCain in opposing Haspel for her confirmation to be in jeopardy.

Warner's decision comes ahead of a Wednesday committee vote on her nomination, which would likely tee up a final confirmation vote in the Senate next week. Warner and West Virginia Sen. Joe Manchin are two Democrats on the committee who are supporting Haspel, and that vote is not in doubt.

Warner announced his backing of Haspel Tuesday after she sent the Virginia Democrat a letter stating the CIA should not have conducted the George W. Bush administration interrogation and detention program.

"While I won't condemn those that made these hard calls, and I have noted the valuable intelligence collected, the program ultimately did damage to our officers and our standing in the world," Haspel wrote in the letter, which was obtained by CNN.

Haspel's confirmation has faced sharp criticism over her supervision of a CIA black site in Thailand where detainees were waterboarded, as well as her role in the destruction of CIA interrogation tapes.

Warner appeared frustrated with Haspel's answers at her confirmation hearing last week, repeatedly asking whether she believed the interrogation program, which critics say amounted to torture, was immoral. Haspel said in the letter that the CIA was not prepared to run an interrogation program and she would not allow the agency to restart one, though she did not weigh in on whether the program itself was immoral.

In his statement, Warner there were "valid questions that have been raised regarding the Acting Director's record, and I have been frank with Ms. Haspel that I wish she had been more open with the American public during this process."

"However, in both our one-on-one meetings and in classified session before the Committee, I found Acting Director Haspel to be more forthcoming regarding her views on the interrogation program," he said.