(CNN) – Former Sen. Chuck Hagel's name has yet to be officially sent to the Senate for confirmation as President Barack Obama's next secretary of defense, yet he faced a wave of skepticism from lawmakers Sunday about past positions on Iran that appear out of line with Obama's own policies.
"A lot of Republicans are going to ask him hard questions," Sen. Lindsey Graham of South Carolina said on NBC's "Meet the Press." "I don't think he's going to get many Republicans' votes. I like Chuck, but his positions are really out of the mainstream and well to the left of the president."
Those positions include opposition to unilateral sanctions against Iran, as well as votes opposing labeling Iran's Islamic Revolutionary Guard Corps as a terrorist organization. He has, however, advocated going through the United Nations Security Council to enact sanctions over Iran's nuclear program.
Hagel's opponents have also struck upon comments that some perceive as anti-Jewish in a 2007 interview, when he said the "Jewish lobby intimidated lawmakers."
The now 5-year-old comment set off a firestorm of protests from Jewish leaders and advocacy groups this week as Hagel's name was increasingly mentioned for the Pentagon's top position.
Hagel has also been receiving a good deal of public support this week, including that of former top military officers and ambassadors in two open letters. Among those praising Hagel's skills for the job are a former national security adviser, retired Lt. Gen. Brent Scowcroft; Ryan Crocker, former U.S. ambassador to Iraq and Afghanistan; and four former U.S. ambassadors to Israel.
Graham said he was reserving judgment himself until after any hearings with Hagel, who sources said has met with both Obama and Vice President Joe Biden and is considered a front-runner for the Defense post. Hagel represented Nebraska as a Republican in the Senate from 1997 to 2009.
"I'm going to wait and see what happens in the hearings," Graham said. "I've got questions about Chuck's view of Iran, Hamas and Hezbollah, his position toward Israel, Afghanistan. I want to hear what he has to say. But very troubling comments by a future secretary of defense."
Sen. Joe Lieberman, an independent from Connecticut, is retiring at the end of the current session of Congress and won't have a vote on a potential Hagel nomination. He said Sunday that Hagel's past positions didn't "disqualify him" for a post at the Pentagon, but that his ideas need serious probing before he gets the job.
"I look at Chuck Hagel's positions on Iran, they seem to me to be quite different than President Obama," he said on CNN's "State of the Union." "Now, President Obama obviously has earned the right to nominate whoever he wants. I think this is a very tough confirmation process. I don't know how it would end, but there are reasonable questions to ask and that Chuck Hagel has to answer."
Democrats appearing on Sunday talk shows largely avoided expressing any opinion of Hagel, saying they would determine their support when and if his name is officially put forward by the president.
Asked directly whether he could support a Hagel nomination, Sen. Chuck Schumer of New York said he'd have to "study his record" further.
"I'm not going to comment until the president makes a nomination," he said on "Meet the Press."
Sen. Amy Klobuchar of Minnesota was similarly noncommittal on ABC's "This Week," saying she would "see what happens with these hearings."
CNN's Mike Mount contributed to this report.