What’s my conclusion? To me, these numbers cast doubt on the analyses that assume that the next Democratic nominee is favored to carry just about every state that Obama did. Obama carried all 12 of the target and quasi-target states listed above in 2008 and in 2012 carried all but North Carolina, where he lost by only 50 percent-48 percent. The apparent drop in Obama approval between 2012 and 2013 suggests that, if the presidential election were held at some point in 2013, all those states would be up for grabs — and a Republican nominee might be leading in most or all of them. But the numbers also raise the possibility that Arizona, Georgia and Texas may become genuine target states. It would be quite a change if Michigan and Pennsylvania (Democratic states presidentially starting in 1992) leaned Republican and Texas (a Republican state presidentially starting in 1980) leaned Democratic.

Remember also that Obama’s current job approval is 43 percent, 3.5 percentage points below 46.5 percent, the Gallup national average for the whole of 2013. The electoral map has been pretty static in the last two presidential campaigns and has not changed a lot over the last four. These numbers suggest that more changes are possible, and that the advantage that Democrats have held in the Electoral College over the last two decades may not turn out to be eternal.