Because the only legitimate argument they have so far to disqualify her is that she is an unqualified idiot who shouldn't be allowed IN a courtroom, much less on the bench.
They can't make that argument about Gonzales, who served honorably on the texas supreme court.
They will still rant about him being insufficiently "conservative" (even though if he's a strict constructionist what he "believes" personally shouldn't matter). But they might be able to stop his nomination, they won't be able to stop confirmation, unless they join forces with liberals who will attack him for supporting the war on terror.
There's the headline we all want, conservatives joining forces with the hate-america crowd to stop a qualified judicial nominee because of his personal beliefs.
What argument would they us against him? Cronyism? Not like them? Too Liberal? Supports Roe v Wade?
Those arguments would ring hollow. After all the howling they have made about Miers not being a judge, not having a paper trail or having a discernable position.