"I don't have litmus tests around any of these issues," he said last month.
But as Elena Kagan continues her one-on-one meetings with senators -- those who will vote her up or down – they clearly want to know where she stands.
Sen. Susan Collins, R-Maine, said she has asked every Supreme Court nominee she's faced, including Kagan, how they feel about Roe v. Wade.
"She said, as did all the previous individuals, that she did consider Roe v. Wade to be settled law," Collins said.
Collins, a member of the so-called "Gang of 14," the bipartisan group that negotiated a deal on the use of filibusters over judicial nominees, said she sees no reason to filibuster Kagan.
Kagan has criticized a 1991 Supreme Court decision that allowed the government to ban the use federal money for abortion . Kagan wrote that the ban amounted to "government hostility toward some ideas."
Though Kagan has no judicial record to examine for clues, anti-abortion groups call her dangerous.
"We're deeply concerned because of her connection avowedly to pro-abortion groups," said Charmaine Yoest, president and chief executive of Americans United for Life. "So it's very clear to us that she's an abortion rights supporter."
Planned Parenthood's endorsement of Kagan would seem to suggest anti-abortion groups have reason to worry. But other abortion rights supporters have yet to be convinced.
"We look forward to learning more about her views on the right to privacy and the landmark Roe v. Wade decision," Nancy Keenan, president of NARAL Pro-Choice America, said in a written statement.
"They are playing their role in the game too," said Matt Bennett of Third Way, a progressive group. "They know exactly what the answers are going to be from Elena Kagan, and what they're really waiting for is for her to rule in cases that come before her."
So what about the meetings with senators and eventual hearings before the Senate Judiciary Committee?
"We need to see her answering questions explicitly about her connections to pro-abortion groups," Yoest said.
But Bennett doubts the such questioning is productive.
"These hearings do a lot of things, but fleshing out where nominees stand on abortion is not one of them," Bennett said.