(CNN) – Sen. John Barrasso said Sunday that when Republicans held up a vote last week on Chuck Hagel's nomination to be defense secretary, it wasn't a political ploy, but a sign of serious questions about the nominee.
"I have grave reservations," Barrasso said on CNN's "State of the Union." "I think he's been wrong about Iran, wrong about Israel, wrong in Iraq, wrong with nuclear weapons. I absolutely plan to vote against him."
The Wyoming Republican argued Hagel, who will likely be confirmed despite the GOP opposition, is going to be "less effective (at the Pentagon) because of the fact that the president nominated him."
"There were a lot of Democrats on Capitol Hill that don't believe he was the best choice. I'm sure the White House is very disturbed with how poorly he did during the confirmation hearing," he said. "I think it is going to impact him as he tries to limp across the finish line to get confirmed."
Hagel has taken heat for not previous statements and positions, including his refusal to back unilateral sanctions against Iran in the past, though he said in his confirmation hearing that he supports the president's sanctions strategy. Others have questioned his association with an anti-nuclear proliferation group that calls for an elimination of all such weapons.
Most Republican senators voted Thursday not to end a filibuster against Hagel's nomination, with the next vote expected to take place February 26, after the Senate returns from recess. Many Republicans said by that time, they will be ready to move ahead and hold a final vote on Hagel.
Multiple reasons have been given for the delay on Hagel's nomination. A trio of Republican senators - Sens. John McCain, Lindsey Graham and Kelly Ayotte - refused to commit to a vote until they got answers from the White House on the September attack in Benghazi, Libya. They received those answers on Thursday.
Others, such as Republican Sen. Ted Cruz, argue that Hagel has yet to provide certain financial disclosures requested by the Senate Armed Services Committee.
Graham went further Sunday and described Hagel on Fox News as a "radical."
"We're doing our job to scrutinize, I think, one of the most unqualified, radical choices for secretary of defense in a very long time," Graham said.
McCain on Thursday said GOP opposition also stemmed from "ill will" toward Hagel over the former senator's criticisms of then-President George W. Bush and the Iraq troop surge. McCain added that Hagel "was very anti his own party and people."
"People don't forget that," McCain said.
White House Chief of Staff Denis McDonough said Sunday he has since spoken to McCain and believes the senator will ease up on his rhetoric and vote to end the filibuster when the Senate gets back from recess.
"I think Sen. McCain and others know that we all have to work together to get this thing done, because when it comes to national defense, national security, that, at least, has to be above politics," McDonough said on NBC's "Meet the Press."
McCain, in fact, conceded Sunday on the same NBC program that he thinks Hagel will be confirmed.
"I don't believe he's qualified, but I don't believe we should hold up his confirmation any further," he said, saying he'll be ready to vote after recess.
Democratic Sen. Jack Reed of Rhode Island, a member of the Senate Armed Services committee, said he didn't think President Obama's pick of Hagel was designed to start a fight. A strong backer of Hagel, Reed pointed to Hagel's experience as a Vietnam veteran.
"I think in fact what's happened is very unusual, unprecedented review, asking for speeches, going back five years, asking for all sorts of material we've never requested of confirmation before," he said on CNN. "We're confident that we'll get the confirmation concluded when we return at the end of the week."
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