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President Obama has dubbed his Supreme Court pick, Elena Kagan, as a "trail-blazing leader," but critics have dubbed her a somewhat unknown quantity.

"Elena is widely regarded as one of the nation's foremost legal minds," the president said at the White House while standing alongside his nominee.

"She's an acclaimed legal scholar with a rich understanding of constitutional law. She is a former White House aide, with a life-long commitment to public service and a firm grasp of the nexus and boundaries between our three branches of government."

Kagan is the nation's current solicitor general, whose role it is to argue government cases before the Supreme Court. White House Press Secretary Robert Gibbs told reporters Monday that to avoid a conflict of interest, Kagan will recuse herself in about a dozen cases this term and less than half in the term after that. White House Counsel Bob Bauer says such recusals are "by no means debilitating."

Senator Susan Collins (R-ME) agrees with Mr. Obama that Kagan's legal background looks good on paper, but she says there aren't enough pages in the stack, "Ms. Kagan has an impressive resume of dedicated public service and strong legal credentials but she does not have extensive writings by which one can assess her judicial philosophy."

Kagan has never been a judge. While that is not unheard of-- former Chief Justice William Rehnquist was never a judge-- it's been decades since a non-judge has ascended to the nation's highest court.

"I don't think the president has one bit of hesitation" that Kagan is lacking judicially, says Senior White House Advisor David Axelrod. He calls Kagan, "one of the foremost legal scholars in the country," saying she's "supremely qualified."

Prior to becoming Solicitor General under President Obama, Kagan was dean of Harvard Law School. It was there where she supported the ouster of military recruiters on campus due to her distaste for the military's "Don't Ask, Don't Tell" policy banning homosexuals from serving openly.

Republican Senator and Judiciary Committee Member Jeff Sessions (Alabama) says that could be a problem for Kagan. But at his briefing Monday, Gibbs countered that the bid was not successful, "There was never a pause in military recruitment [at Harvard]."

Sessions is also wary that a nominee like Kagan may become a mere mouthpiece the president's agenda, "The key thing is, does this person have the kind of understanding of the law; that they are supposed to be a neutral arbiter of disputes, to not take sides, that does not see the opportunity to sit on the Supreme Court as one to advance certain political agendas?" he posed on Fox News Channel.

"This is the antithesis of law and I think that will be a fundamental question we will inquire into."

While at Harvard, Kagan also made a move that President Obama seems to feel could entice Republicans to support her. "At a time when many believed that the Harvard faculty had gotten a little one-sided in its viewpoint, she sought to recruit prominent conservative scholars and spur a healthy debate on campus," the president said.

Kagan is expected to be confirmed, but Senate Minority Whip Jon Kyl (Arizona) warned against jumping to conclusions, "As I made clear when I supported her confirmation as solicitor general, a temporary political appointment is far different than a lifetime appointment to the Supreme Court."

Either way, President Obama isn't taking any chances. While he tasked his chief of staff to inform various Senators about his choice of Kagan, he chose to call Massachusetts Republican Senator Scott Brown himself.

Kagan was Harvard Law's first female dean. If confirmed, she will become the fourth woman to ascend to the Supreme Court. Axelrod said Kagan's gender and relatively young age, she's 50, were important factors "but not determinative."

What is important to this White House is the role she'll play on the bench. Known by some for her skills of persuasion, Kagan will play a leadership role on the court, says Bauer. She'll go "toe-to-toe...on very difficult issues and [will] chart a constitutional path [with] imagination and keen intellect."

With no judicial record to parse, Senators are left to focus on what information they do have, which could encompass Kagan's ideology. But ideology shouldn't be a factor in her confirmation, White House officials say, because it "over-simplifies" the decision-making dynamic of the court.

Speaking of ideology, when Fox's Senior White House Correspondent Major Garrett asked if Kagan is a "center-left" nominee, both Axelrod and Bauer refused to bite.