WASHINGTON (AP) — Senate Republicans sent the clearest message yet to President Barack Obama that he would have a second-term confirmation fight if he nominates U.N. Ambassador Susan Rice to replace Hillary Rodham Clinton as secretary of State.

"We will do whatever is necessary to block the nomination that's within our power as far as Susan Rice is concerned," Sen. John McCain, the top GOP senator on the Armed Services Committee, told reporters at a Capitol Hill news conference.

Said Sen. Lindsey Graham, R-S.C.: "I don't trust her."

The two lawmakers along with Sen. Kelly Ayotte of New Hampshire are pressing for a special, Watergate-style select Senate committee to investigate the Sept. 11 attack on the U.S. consulate in Benghazi that killed U.S. Ambassador Chris Stevens and three other Americans. They complained that separate inquiries by various Senate panels will fail to get to the truth and a comprehensive probe "up to and including the president of the United States" was warranted.

They planned to introduce a resolution calling for the special committee on Wednesday afternoon. However, they face opposition from Democrats.

Senate Majority Leader Harry Reid, D-Nev., said a select committee is not necessary.

Pressed on reports that Obama is considering Rice for the top job at the State Department, the GOP lawmakers were withering in their criticism of her response to the Sept. 11 attack, citing her comments five days after the incident that it was the result of an angry response in the Arab world to an anti-Muslim video.

McCain said the information that Rice relayed on the Sunday talk shows was false and she should have known that it was a terrorist attack.

Graham argued that it makes no sense to promote "anybody who was an essential player in the Benghazi debacle." The lawmaker said he has not been impressed with her work at the United Nations, contending that Russia and China have ignored the United States.

Graham said Rice is more of a "political operative" than a candidate to be the nation's top diplomat.

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