It seems likely following a Republican victory in the House that the GOP won't simply be satisfied by preventing the administration from closing Gitmo, but that they'll try to prevent the administration from transferring anyone out of the facility at all. As Liza Goitein points out, this violates some very basic democratic sensibilities and would involve defying the will of the Supreme Court, but as with calling for all terror suspects to be tried by military commission it's also another example of Republicans adopting an unsustainable and irresponsible policy to the right of the previous Republican administration.
Almost 800 people have been imprisoned at Gitmo, whereas there are only about 170 detainees left. The vast majority were released under Bush, and even the exaggerated government "recidivism" rate pegs detainees who have become involved in terrorism since at 20 percent, or 1/3 of the recidivism rate for prisoners in the U.S. Either Gitmo has some really serious rehabilitative qualities or the vast majority of those imprisoned their were innocent.
Now it goes without saying that the new crop of "small-government" conservatives aren't moved by entreaties to inalienable individual rights when it comes to Muslims accused of terrorism, but they're also not moved by cutting costs either, since it costs American taxpayers $650,000 a year to imprison a single detainee, compared to about $5,575 for a federal inmate.
At the very least, you'd think they'd reconsider in light of the fact that the source of the tip that foiled the recent mail package bomb plot came from Jabir al-Fayfi a former Gitmo detainee who may have been a false recidivate. It's not clear that he was a double agent to begin with, but preventing any transfers from Gitmo will certainly eliminate the option of intelligence agencies planting false recidivates among radical groups eager to claim such individuals for their value as propaganda symbols if nothing else.