U.N. Ambassador Susan Rice returned to Capitol Hill on Wednesday for a fresh round of face-to-face meetings with her Republican critics, and once again failed to find the public support she would need to secure her confirmation to serve as the next secretary of state.

As with meetings she held Tuesday, Rice discussed her role in the Obama administration’s response to the Sept. 11 U.S. consulate attack in Benghazi, Libya, specifically comments she made five days afterward regarding the origins of the assault. Rice’s involvement in the administration’s response is complicated by the fact that President Obama is reportedly considering her to succeed Hillary Rodham Clinton at the State Department.

Rice met Wednesday morning with Sen. Susan Collins (R-Maine), who is the ranking member on the Senate Homeland Security and Governmental Affairs Committee, which is investigating the Libya attack. She also met with Sen. Bob Corker (R-Tenn.), a senior member of the Senate Foreign Relations Committee.

After a 75-minute meeting with Rice, Collins told reporters: “I still have many questions that remain unanswered.”

Collins said she was “troubled” that Rice, in her role as U.N. envoy, “decided to play what was essentially a political role at the height of a contentious presidential election campaign” by appearing on five political talk shows to present the administration’s position.

Collins also noted that Rice was working at the State Department in 1998 — and was the assistant secretary for African Affairs — when U.S. embassies in Kenya and Tanzania were bombed. Requests for additional security at both outposts had been denied and Collins said she asked Rice on Wednesday whether she had been involved in those decisions.

“She [Rice] said she would have to refresh her memory, but that she was not directly involved in turning down the request,” Collins said. But the senator said Rice must have been aware of the requests.

Collins demurred when asked if she would be able to support Rice if she is nominated by  Obama to serve as the next secretary of state: “I would need to have additional information before I could support her nomination. She’s not been posted yet, our homeland security committee investigation is ongoing, there are many different players in this and there’s much yet to be learned. So I think it would be premature for me to reach that judgment now.”

For his part, Obama on Wednesday once again voiced support for Rice. Asked by reporters during a White House Cabinet meeting whether he still supported his U.N. ambassador, Obama said: “Susan Rice is extraordinary.” With that, the rest of his Cabinet applauded.

“I couldn’t be prouder of the job that she’s done,” he added.

Back on Capitol Hill, Corker said Obama should nominate whoever “he thinks is best suited” to serve as his next top diplomat.

“I am asking the president to step back away from all that’s happened and take a deep breath and to nominate the person that he really believes is the very best person to be secy of state for our country, regardless of relationship,” Corker said.

But Corker said he remains troubled by the administration’s response to the Libya affair: “Whenever I’m in contact with anyone who has anything to do with either the intelligence, the communication, anything involving the way Washington itself has handled Benghazi, whenever I’m around anybody who’s had any close relationship, I will say that emotion within me rises tremendously.”

Corker said so much of the GOP’s attention has focused on Rice “because she ended up being the spokesperson five days later.”

This item has been updated since it was first published.

Rosalind S. Helderman and David Nakamura contributed to this report.

Follow Ed O’Keefe on Twitter: @edatpost

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