ALL nominations to the Supreme Court MUST be approved by Congress.

The nominations are made by the President, "with the advice and Consent of the Senate."

Senate Procedure

Despite the fact that certain procedures for the Senate's advice and consent function were established the first time George Washington and the Senate interacted on nominations, other procedures have only come into being more recently. Today when the Senate receives a Supreme Court nomination from the president, the nomination is referred to the Senate Judiciary Committee for hearings, but that has been a regular procedure only since 1949. Until then, hearings were help only sporadically, usually in an instance where some controversy had arisen regarding a nomination. A major part of the Committee hearings is the testimony of the nominee, but that has been a regular feature of the hearings only since 1955. Of course, we can watch the hearings live on television, but that has been the case only since 1981.

It is expected that the Committee will make a recommendation to the Senate, whether that recommendation be to confirm or to reject. That too has not always been the case. A common method of quashing nominations to the lower federal courts is simply for the Committee not to report on the nomination, to kill it in committee. That is unlikely to happen with a Supreme Court nomination today. Even is the majority of the Committee is in opposition, they likely will report it to the full Senate as a recommendation to reject the nomination.

Upon receiving the recommendation of the Judiciary Committee, the Senate leadership will schedule a debate and a vote on the nomination. In a noncontroversial nomination, like that of Ginzburg or Breyer, only a few senators will rise to praise the nominee before proceeding to the vote. In a more controversial nomination, more senators will rise in support of or opposition to the nominee.

There doesn't seem to be any provision in the US Constitution for any temporary or other sort of appointment.