"If he's saying that he wants to pick people who will take sides -- he's also said that a judge has to be a person of empathy. What does that mean?" Hatch asked. "Usually that's a code word for an activist judge."
Sen. John Ensign, R-Nev., said on "Fox News Sunday" that "too many times, people on the Supreme Court and even in the Court of Appeals -- they have been making laws based on what they want to see in the Constitution, not on what the Constitution says.
"And that's what we have to get back to, is actually having people who look at the law and they read it for its plain reading," what the founders intended, he said. "They read it for what judicial precedent has been, instead of just what they want to see in the law."
But beyond ideology, the expectation to diversify the court is perhaps even more prominent since Obama is the first African-American president.
Leahy, also appearing on CNN's "State of the Union," said he and his wife drove to Vermont on Friday, expecting it to be "a nice, quiet time."
Instead, he said, "it was like a phone booth in our car all the way up with all these different groups, everybody else calling about who should be there" on the court.
From Solicitor General Elena Kagan, the former dean of the Harvard Law School, and Kathleen Sullivan, former dean of Stanford Law School and co-founder of the school's Constitutional Law Center, to federal appeals court judges Sonia Sotomayor, who would be the first Hispanic justice if nominated and confirmed, and Diane Wood, the names crossing the lips of Washington insiders speculating on who the pick will be have been the names of women.
Hatch said on "This Week" that he didn't necessarily agree with conservative groups who labeled some of the women "radicals," but said "there's no question that they are on the far left of the spectrum."
"I don't expect the president to pick somebody in the center or on the far right," he continued. "But, you know, it would be a slam dunk if he picked somebody who was center-left like Souter. Souter became very liberal, but he also stood for a lot of principles."
And Hatch contends that some of Obama's criteria are bothersome.
"He's bright enough to know that those comments basically indicate that politics, preferences, personal preferences and feelings might take the place of being impartial and deciding cases based upon the law, not upon politics."
But with all the politics and pressure, the expectation and anticipation, Leahy looks back to Souter's confirmation process for a lesson.
"You will hear a lot on the far right or the far left who will say who he should or shouldn't go with. Remember, a lot of the left-wing groups picketed, actually picketed the Senate building that I'm in against me, because I was going to vote for David Souter," he said.
"They said it would be terrible, the end of the world if we confirmed David Souter," Leahy continued. "Now those same groups think David Souter was a great justice."
"The fact of the matter is that the president will make a good choice."