As Democrats pressed Monday for an early August vote to confirm Solicitor General Elena Kagan as the next Supreme Court justice, skeptical Republicans began casting doubt on her qualifications for the job.

Sen. Patrick Leahy, D-Vt., the Judiciary Committee chairman, called Kagan, 50, a "superbly qualified candidate" who would "obviously" be confirmed this summer before the chamber leaves for a monthlong break. His panel will hold Kagan's confirmation hearings, and Democrats have more than enough votes to elevate her.

Republican leaders made it clear, however, that they're in no hurry to vote on President Barack Obama's pick, whom some of them criticized as insufficiently experienced to serve on the high court. One GOP senator, James Inhofe of Oklahoma, already has decided to oppose her nomination.

Americans "instinctively know that a lifetime position on the Supreme Court does not lend itself to on-the-job-training," said Sen. Mitch McConnell R-Ky., the minority leader. He was echoing the language then-presidential hopeful Hilary Rodham Clinton used to question Obama's fitness for the Oval Office during the 2008 campaign.

"Fulfilling our duty to advise and consent on a nomination to this office requires a thorough process, not a rush to judgment," said McConnell, promising that his party would treat Kagan fairly.

Kagan, the former Harvard Law School dean Obama nominated to succeed retiring Justice John Paul Stevens, has never been a judge. While Democrats touted that background "outside the judicial monastery" as a plus that would bring a diversity of perspective to the Supreme Court, Republicans questioned whether she had the skills necessary to be a justice.

"The fact that she is not a judge is not disqualifying," but coupled with her inexperience as a courtroom litigator, it "does present a weakness," said Sen. Jeff Sessions of Alabama, the top Judiciary Committee Republican.

He said a vote to confirm by early August is "doable," but that Republicans would not be rushed and were preparing to provide "the loyal opposition" in the upcoming debate.

With midterm elections as a backdrop, Kagan's confirmation process has the potential to devolve into partisan proxy fight that highlights Democrats' and Republicans' differing views about the role of a Supreme Court justice, and precedents on hot-button issues ranging from abortion to political speech.

Still, barring extraordinary circumstances, Kagan should win Senate confirmation on the strength of Democrats' numerical advantage. Democrats control the chamber with 59 votes, one short of what they would need to forestall the possibility of a partisan filibuster.

Leahy noted that both Chief Justice John Roberts and the newest justice, Sonia Sotomayor, were confirmed swiftly in time for the start of a new court term. He said the same should be done for Kagan.

"The decisions made at the nation's highest court affect the daily lives of all Americans," Leahy said. "Our constituents deserve a civil and thoughtful debate on this nomination, followed by an up-or-down vote."

To stop her from becoming the nation's 112th justice, Democrats would have to abandon Obama and his second high court pick, or almost all of the GOP senators would have to agree to block a vote on the nomination _ more than a year after seven of them voted for Kagan to become the solicitor general.

It's unlikely that Republicans will unite to try stop Kagan, although Sessions said it was premature to rule it out. But some of her former backers held out the possibility that they might yet turn against her, saying their previous support wouldn't necessarily translate into votes to confirm her as a justice.

"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," said Sen. Jon Kyl of Arizona, the No. 2 Republican.

Sen. Orrin Hatch, R-Utah, a Judiciary member and another past backer, said Kagan's "previous confirmation, and my support for her in that position, do not by themselves establish either her qualifications for the Supreme Court or my obligation to support her." Hatch said he was keeping an open mind.

Because she spent little time as a litigator and hasn't served as a judge, Kagan does not come with the usual trove of legal briefs or court opinions that normally form the basis for Senate hearings on a nominee's judicial or legal style.

But conservatives are using her resume to paint her as a liberal activist.

"It's downright silly to imagine that a fervent supporter of gay rights who thrived on the Harvard Law School faculty and in the Clinton Administration and embraces Justice Thurgood Marshall's approach to judging will turn out to be a closet conservative once on the High Court," wrote Curt Levey of the Committee for Justice in a memo about her nomination.

If confirmed, Kagan would join Justices Ruth Bader Ginsburg and Sotomayor in bringing the number of women on the Supreme Court to three, the highest in the court's history.

Kagan will immediately begin courting the votes she needs by calling on members of the Senate, beginning Wednesday.

Some Democrat-affiliated groups are concerned that naming Kagan to replace Stevens _ the leader of the court's liberal bloc _ will have the net effect of making the court more conservative.

Kagan's confirmation would "move the Supreme Court to the right," said progressive activist Norman Solomon, the author of "War Made Easy: How Presidents and Pundits Keep Spinning Us to Death."

The solicitor general _ known informally as the "tenth justice" _ represents the United States, including defending acts of Congress, at the Supreme Court and deciding when to appeal lower court decisions.