The House will turn Democrat. The Senate will turn Republican and Obama will win again. That is my guess.
The GOP has the house, so they can pass a House bill to do it. In the Senate, even after the election, they'd have to win 7 additional seats to gain a filibuster-proof majority. Then of course, Romney has to be elected so he can sign the law.
The Senate is the problem. The GOP may pick up seats, but very very unlikely to pick up another 7.
Lastly, if we don't get it done after this next election, it's too late. By Nov. 2014, when the GOP could finally win enough seats in the Senate, ObamaCare will already be fully implemented and just impossible to dismantle.