Brennan was expected to have an easier time on the path to Senate confirmation than Chuck Hagel, Obama's choice to run the Pentagon. A handful of Republicans have announced opposition to their former GOP colleague, and several skeptical Democrats reserved judgment until Hagel explains his views on Israel and Iran.
The concerns about Hagel complicate his path to Senate confirmation but are not necessarily calamitous as the White House pushes for the first Vietnam War veteran and enlisted Army man to oversee a military emerging from two wars and staring at deep budget cuts.
Brennan, a 25-year CIA veteran, is expected to be hit with questions about torture and administration leaks of secret information at his hearing, but is widely expected to win Senate confirmation. Graham's demands on the Libya raid could stall the nomination.
Hagel has upset some Israel backers with his comment about the "Jewish lobby," his votes against unilateral sanctions against Iran while backing international penalties on the regime in Tehran and his criticism of talk of a military strike by either the U.S. or Israel against Iran.
He also upset gay rights groups over past comments, including his opposition in 1998 to President Bill Clinton's choice of James Hormel as ambassador to Luxembourg. He referred to Hormel as "openly, aggressively gay." Hagel recently apologized, saying his comments were "insensitive."
Those remarks and actions have created fierce opposition from some pro-Israel groups, criticism from some Republicans and unease among some congressional Democrats.
In an interview with the Lincoln (Neb.) Journal Star, Hagel said his statements have been distorted and there is "not one shred of evidence that I'm anti-Israeli, not one (Senate) vote that matters that hurt Israel."
During a trip to the Mideast, Sen. Bill Nelson, D-Fla., sought to reassure Israelis concerned about Hagel's nomination. Nelson, a member of the Armed Services Committee, said Hagel has a record of support for Israel.
Nelson said he discussed Hagel's nomination with Israeli Prime Minister Benjamin Netanyahu. He said the prime minister did not voice objections to Hagel.
Former Sen. Max Cleland, D-Ga., himself a wounded Vietnam veteran, said he thinks Hagel "has to clarify" his positions on issues like Iran and Israel.
But Cleland also said in an interview on "CBS This Morning" Tuesday that Hagel is battle-tested and ready for the challenges of a confirmation process, accusing the Nebraskan's critics of "swatting at nothing, shadow-boxing."
Associated Press writers Julie Pace, Darlene Superville, Lolita C. Baldor, Lara Jakes and Connie Cass contributed to this report.
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