Well... some of them are.
In the course of this whole judges thing, some have said that Democrats are opposed to "people of faith". Others have said that that is an inappropriate (and wrong) thing to say, and I agree with them.
However, it does appear that at least one highly-vocal liberal organization -- which apparently has a good deal of say in the Democratic Party -- does think there's a problem with having religious judges. See this.
And as I've said before... it's pretty clear that the consequence and implication of the Democratic senators' actions is that no Christian who upholds traditional Christian beliefs on various moral issues is fit to be a judge.
Update: the picture has been removed. No surprise... it was a picture of Pope Benedict, editted to show a gavel in his hand, and him standing before the doors of the Supreme Court, with the words "God already has a job.... He does not need one on the Supreme Court. Protect the Supreme Court Rules" above his head.
I'll link it if someone puts it up elsewhere. Newer Update: here it is!