There's a reason why the Republicans may not want to win anytime soon. The problems the country confronts are considerable, and none of them can be solved without significant costs. For now, of course, much of the blame for all this is on the Bush administration. And so for the immediate future, Obama will be given a considerable amount of slack and flexibility. But that won't last forever. By 2012, Obama will have to have made some considerable progress on many fronts to get re-elected.
This is a high risk strategy of course. If Obama is perceived as successful--if unemployment is down to a more tolerable level, say under six percent, if most of US troops are out of Iraq and Afghanistan looks at least solvable, then given Obama's electoral coalition and demographic shifts, you'll be looking at Democratic dominance for at least a decade or two.
Indeed, the strategy has really never worked. Presidents who have come in during times of crisis and succeeded not only won re-election, they changed the electoral map--Lincoln, Roosevelt, and Reagan are obvious examples of this. Hoping that Obama is another Carter strikes me as pretty desparate.