Ezra explains it:
Insofar as there’s a long-term strategy here, it comes down to 2014. Republicans feel that this is a defensive year for them, and if they can resist further tax increases while locking in some spending cuts, that will be more than they could reasonably have expected in the days after the election. But in 2014, they expect the implementation of Obamacare to be a debacle that will give them an opportunity to mount a policy offensive against the White House. If they can just get through this year and get to 2014, their position will strengthen considerably.
Tomasky’s imagines what Republicans are thinking:
As long as we can gum up the works, make it look like Washington can’t do anything, deny Obama any sort of breakthrough victory, then we can head into ’16 in a strong position. We can say the country needs new leadership, the Democrats weren’t able to govern.