The fundamental flaw in your analysis is that you assume that the moderates in their hearts want to vote with the president on Supreme Court nominees and that the compromise is just a way of getting there. In fact, it is just the opposite.
The real problem is that the R's in the compromise like the Supreme Court just the way it is. They don't want a conservative majority on the Court. For example, several of them are explicitly pro-abortion. Lindsay Graham is probably homosexual and I suspect he has the Andrew Sullivan problem with a conservative Supreme Court--it wont impose Gay Marriage on the country.
Their dilemma is, to get the Court they want (more of the same), they have to buck their president and there might be a political cost for doing it. (I except McCain from this analyis. His motives look to be pure spite and a pipedream that he can be president in 2008. I don't think he cares about the composition of the supreme court one way or the other).
The compromise was exquisitely designed to help the moderates vote for the supreme court they want (a leftist court) with as much political cover as they can concoct from the Old Media and their buds in the democrat party. So they pose the issue as being a matter of 'holding the middle', 'rejecting theocracy' and 'voting for the traditions of the senate.' So they are brave and principled for doing what they have done and intend to do. Frankly, they have played it beautifully.
If things continue going as they are, we lose the Supreme Court because of this elegant piece of political gamesmanship. The only way we come out of this with a decent Supreme Court is if we convince enough of the seven (and Specter and Hagel) that they will pay an enormous price for bucking the party. The only way to do that is as follows:
(1) The administration has to convince them that it is going to keep sending Brown/Owen/Estrada type nominees and that the moderates are not going to intimidate him into say, a Gonzales.
(2) The Senate Leadership has to convince them that it will continue to force votes and require them to take a stand on the record over and over. The Senate leadership has to be willing to lose a cloture vote and the nuclear option and to keep coming back and trying again.
(3) Conservative voters have to convince them that we will crawl across broken glass to destroy their political careers, their children's political careers, and anything else of theirs we can get our hands on if they buck the President.
If all three of these conditions hold, we can regroup from this very terrible defeat because they will blink. If not, we will have a liberal supreme court for the next 20 years driving us inexorably to Gomorrah.
modelbreaker- you are so right about how this group of nitwits, including the head of the Cockroach Republicans, Lindsey Graham, DO NOT WANT a conservative Supreme Court.
Can't recall the exact language Graham used on Sean's show the other day, but I definitely came away with the message that he---the All Powerful Him Upon Whose Cojones The Fate of the Judiciary Now Rests (now that all deals must come through him---did not want "those people" on the Court.