Bush sent up over 180 nominations. They did not consider about 80 of them at all.
The process is those nominations are to get a hearing before the judiciary committee. If the judiciary votes to approve after a hearing, then the full senate votes to confirm or deny. If the Judiciary committtee votes no, the candidate is normalay rejected. Unless 60 senators want a floor vote for confirmation, they can bring a motion that will force the senate to have a floor vote for confirmation.
Leahy as chairman would not schedule committee hearings for 80 of bush's appointees. Thus there never was a hearing or vote in the committee for those 80 nominees. Of the 102 that had hearings, 100 were approved by the committee and sent to the full senate for a vote. When the full senate votes is up to the Majority leader. Daschle stalled on these votes as long as he could.
A single senator can put a hold on a nomination and no vote will be taken for the two weeks the hold is in effect. The Democrats took turns puting holds on nominations.
The senate was made very difficult to manage by our founding fathers. They did it on purpose. They made so that it takes a very unified senate and both parties support to do almost anything.
The Democrats can do it because our founding fathers gave them the power to do it. The founding fathers believed in limited government. Since the senate has to pass all bills and confirm all judges they made it a very hard thing to do.