My call on "shared sacrifice"
I think Team Obama will try to give just enough of the middle class just enough incentive to keep them on board the O train through 2016. And since "it would be irresponsible not to speculate" (Peggy Noonan)--
The lesson of 2012 IMNSHO is that a party can put together slivers of support to reliably and predictably win by 2 or 3 percentage points; "money ball," see Nate Silver. A landslide isn't needed and isn't even desirable, since parties wish to become beholden to as few voters as possible; voters are, after all, not their real constituencies. The auto bailouts in 2009 provide an example: They were IMNSHO, whatever else they were about, about the swing states of OH and MI in 2012: slivers. (The "tell" here is that the states and localities were NOT bailed out, even though that could have decreased unemployment by at least a point. Not slivers. Also too privatization/shock doctrine/union busting especially teachers.) Therefore, the "shared sacrifice" of 2012 will be all about accumulating slivers of support in 2016, at least in terms of the policy proposals the administration presents.
Those one rung down the ladder -- too needy and/or in the "wrong" slivers -- will be kicked down or thrown off the ladder, exactly like "discouraged workers" have been. (That to me is the lesson of ObamaCare, its phased implementation, and the reactions of those who had the good luck to be "vested" in the initial phases to those who will be mandated to participate in the later phase.)
Solidarity or even simple humanity ("public purpose" may be preferred) is not a value anyone is appealing to here, even if "a rising tide of empathy lifts all boats" (as can be shown with health care, and with jobs guarantee vs. unemployment as "buffers").
The bright side is that for all the talk of demographics leading to a permanent majority for Obama-ism and the "market state," we are really seeing a sort of bricolage -- that's what all the data-driven microtargeting is about.* And bricolage is fragile; shake (to change metaphors) the kaleidoscope and the pattern changes radically and at once.
NOTE * 2008 vets: Microtargeting (within the technological limits of the day) was Mark Penn's bailiwick. BWA-HA-HA-HA-HA!!!!!