***I suspect this means Frist didn't have the votes - which means he lost 5+ votes from Republicans.***
I suspect you may be correct. However, IMO he should have made the attempt so that we may know just where the individual Republicans stand.
The likely candidates are Snowe, Collins, Chaffee, McCain and Hagel. I'm inclined to believe that Frist extracted a promise of support from Specter before allowing him to accede to the Judiciary Chair.
Nonetheless, in terms of setting the Senate's rules of procedure, 50 votes wouldn't be enough. Cheney would have no vote in this affair. The GOP needs 51 votes to accomplish their objective.
Perhaps Frist has them. But not to change the Senate's rules of procedure. Instead, he might have them to sustain a point of order -- should the Democrats actually attempt another filibuster and the question is called as to whether judicial nominees require more than a majority vote.
In that case, Frist may well have the votes to sustain a ruling by the chair (Cheney). It achieves the same end, it's almost the same thing...but not quite.
In other words, one or two RINOs may want to actually see the Democrats try to obstruct the procedure -- before they cut them off.