I believe that the Republicans have chosen the wrong tactic but the right strategy. By making their opposition to the ACA strong, vocal, repeated and persistent, they are staking a clear position on a law that is in all likelihood a complete and total clusterfuck. However, they're destroying the positive political capital that they can reap from that in the midterm elections next year by shutting down the government.
If the ACA is as bad as they say (and I agree with them that it is), Americans now know where the Republican Party stands on the issue. Let the Democrats double down and lose in 2014, but get the government up and running again. If it isn't the complete nightmare that it is shaping up to be, then the Republicans should stop obstructing things. Either way, the better tactic right now is to step aside and let things take their course. That way, the Republicans can position themselves to sweep the House and Senate in 2014 (well, the Senate to the extent they can based on what states are up). They can then destroy the ACA and all Obama can do is veto bill after bill after bill, against the backdrop of rising public anger that the ACA is still in place.
ἡ δὲ κἀκ τριῶν τρυπημάτων ἐργαζομένη ἐνεκάλει τῇ φύσει, δυσφορουμένη, ὅτι δὴ μὴ καὶ τοὺς τιτθοὺς αὐτῇ εὐρύτερον ἢ νῦν εἰσι τρυπώη, ὅπως καὶ ἄλλην ἐνταῦθα μίξιν ἐπιτεχνᾶσθαι δυνατὴ εἴη. – Procopius
Ummaka qinnassa nīk!
*MySmiley*