Blue Commonwealth has the rundown of all the options President Obama and Democrats face going forward.
I like the "faux populism" idea, focused on thoughts that Democrats haven't done enough to excite their voters.
This is the famous Obama gap, noticed in Virginia and New Jersey, where the Obama voters simply failed to show up at the polls. Even after allowing for possible leftward bias by MoveOn.org and for the known liberal tilt of Massachusetts, these figures seem to make the point that the apparent voter anger boiling up across the country is a populist anger. They voted for Obama in 2009 because of his promise to change things to the benefit of workers and the middle class. They voted for Brown in 2010 because they were frustrated by Obama's failure to deliver, and Brown ran a populist campaign (maybe a phoney one, but nonetheless he punched the right buttons). In other words, the voters did not reject the Obama agenda.
If Brown voters are populist, then there's room for progressives and those they call "teabaggers" to work together. It will probably work better if they stop calling fellow voters "teabaggers."
We'll see which "big" the populist anger is focused on - "big business or big government." If big government is the focus, Obama's got a lot tougher job ahead.