The decision regarding whether the Senate Judiciary Committee or the Senate as a whole should vote in favor of a nominee to the U.S. Supreme Court is a purely political question. There are no binding criteria and the decision is not subject to judicial review.
Each Senator sets his or her own standards, although the Senate Judiciary Committee also would prefer not to approve a candidate whom the full Senate is likely to reject.
All previous U.S. Supreme Court nominations in recent history, except the nomination of Judge Gorsuch, that were considered by the Senate Judiciary Committee and the full Senate also took place in a context when any nominee had to overcome a filibuster threat to be considered on the merits by the U.S. Senate, a limitation that no longer applies. So, the Senate Judiciary Committee was once considering if a nominee of the majority's own party could secure 60 votes, some from members of the other party, while now it need only consider whether the nominee can secure 50 votes plus a Vice Presidential tie breaking vote from members of their own party. So, the standard to approve a nominee has loosened somewhat, at least in theory.
The vast majority of U.S. Supreme Court nominees have been confirmed.
The isolated cases in recent history where a nominee has not been confirmed (e.g. Judge Bork and Judge Garland), or where the vote in favor of a nominee was close (e.g. Justice Thomas or Justice Gorsuch), are sufficiently individualized and in some of the cases are so long ago, that they don't provide very clear precedents today.
U.S. Supreme Court nominees do, however, tend to be scrutinized more carefully than appointees to cabinet positions, because of the political power associated with that appointment and the fact that it is a lifetime appointment.
There are factors that individual Senators often consider, but none of those are binding or uniform among Senators, and those that are widely accepted are not necessarily applied in the same way by different Senators.
In general, Senators tend to opposed nominees who they perceive as too extreme in judicial philosophy in a manner opposed to their own views.
Senators also expect nominees to be licensed attorneys who had successful careers prior to their nomination (and to lack any clear evidence of incompetence or other conduct that would be grounds for disbarment or removal from judicial office), to have a "judicial temperament", and to be willing to commit orally in their testimony to being impartial in interpreting and applying the law if appointed (whether or not their background and history as a judge supports this claim).
These criteria, other than judicial philosophy, do not pose much of an issue for most nominees.
Nominees generally refuse to offer testimony regarding their opinions on unresolved legal issues that are likely to come before the court and Senators normally don't consider that refusal to be disqualifying.
