A showdown is brewing in the Senate over the vote to confirm former Sen. Chuck Hagel as secretary of defense.
A vote is expected Friday, and Democrats hold a 55-45 edge over the Republicans.
However, it takes 60 votes to end debate and hold a vote. Some Republicans, like Sen. Lindsey Graham of South Carolina, are suggesting they'll block it.
Graham said he wants President Obama to answer questions about his activities on the night of the Sept. 11 attack in Benghazi, Libya, that left four Americans dead.
Many Republicans oppose Hagel's nomination. Even Maine's moderate Sen. Susan Collins has now issued a statement against him.
Collins said she's concerned because he was unwilling to designate Hezbollah a terrorist group in 2006.
"I am unable to support Senator Hagel to be the next secretary of defense because I do not believe his past positions, votes, and statements match the challenges of our time, and his presentations at his (confirmation) hearing did nothing to ease my doubts," Collins said.
"I regret having to reach that conclusion given our personal relationship and my admiration for Senator Hagel's military service," she added. "But I have concluded that he is not well-suited for the tremendous challenges our country faces during this dangerous era in our history."