Washington (CNN) Republican Sen. Jeff Flake announced Wednesday he will vote against Gina Haspel's nomination to be the next CIA director, becoming the third senator from President Donald Trump's own party to come out against his choice to lead the agency.

The Senate Intelligence Committee voted 10-5 behind closed doors Wednesday to send Haspel's nomination for a full floor vote, where she looks all but assured to win Senate confirmation. Two of the committee's seven Democrats had said they supported Haspel, including Virginia's Sen. Mark Warner, the top Democrat on the panel. Haspel currently has more than enough support to win confirmation, as Warner was one of six Democrats who've announced they plan to vote to confirm her. Sen. Jeanne Shaheen of New Hampshire became Haspel's sixth Democratic supporter shortly after Flake's announcement.

Flake's no vote follows Kentucky's Republican Sen. Rand Paul, who also said he'd oppose the nomination, and Arizona's GOP Sen. John McCain, who released a statement asking senators to vote against Haspel but is unable to vote himself because he's in his home state battling cancer.

"While I thank Ms. Haspel for her long and dedicated service to the CIA, as a country we need to turn the page on the unfortunate chapter in the agency's history having to do with torture," Flake said in a statement. "Congress needs to be able to provide fully informed oversight. My questions about Ms. Haspel's role in the destruction of videotapes relevant to discussions occurring in Congress regarding the program have not been adequately answered."

Haspel faces opposition from a majority of Democrats and human rights groups for her role in the George W. Bush administration's interrogation and detention program, which critics say amounted to torture.

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