Real median household income is still considerably lower than it was prior to the Recession. Things are slowly improving, but the average household (well, the median household, but you get the expression) is still poorer that it was before the crisis:
The Dems could try to argue that the recession would've been much worse without the stimulus etc (but that's old news so I doubt it would get them many votes) but trying to spin the current situation as a time of prosperity for most people would not go over well.
You're right about the energy boom, but can Obama really be credited with that? To be fair, no President can (or at least, no President should) be directly credited with economic developments of this nature but many people perceive Obama as an anti-oil/gas guy and a Dem advertising campaign stressing the energy boom probably wouldn't work too well since the don't really have any specific policies to attribute the boom to and it'd be pretty hard for them to beat the GOP at their own game in regard to energy.