Do you think Dem Senators should vote for or against John Roberts for the Supreme Court?

I don't mean "do you want Roberts on the Supreme Court?" I certainly don't want him there. My question is somewhat different.

Do you think the Dems should vote for or against Roberts, not based on substance, but based on what the politically smart vote would be. (We all agree that, on substance, we don't like him.) But by politically smart, I mean the following...

I want to thwart Bush and the radical right packing the court with far-right judges who would unravel many of our basic freedoms and rights. What's the best way to achieve that goal? Roberts will win confirmation, we know that. So what's the best way to ensure that the NEXT judge Bush nominates will be a "uniter," and if he or she isn't, what's the best way to ensure that they don't win confirmation?

Do Dem senators vote against Roberts in order to send a signal that the country won't tolerate Bush trying to move an already conservative court further to the right (and also send the message that we won't permit judicial nominees to simply stonewall and not answer any serious questions)? Or do senators vote FOR Roberts and say "this is the last time, you got your conservative to replace another conservative (Rehnquist), but next time you're replacing O'Connor and you'd better give us a moderate to replace a moderate?"

Will the Dems have more credibility opposing, perhaps even with a filibuster, a future nutjob appointment by Bush if they vote FOR Roberts now? Or will they draw the line better by voting against Roberts now?

Your thoughts?