At this point, it's beginning to look likely that the U.S. unemployment rate will still be around 8% when the next presidential election occurs in November 2012. That presents a serious challenge for President Obama. He'll have to convince voters that the very high rate and prolonged nature of unemployment isn't his fault. To some, complaining about the mess he was left by the previous administration after four years in office will wear thin? But the difficulty he has in battling sour economic sentiment will likely vary from state to state.

U.S. presidential elections are tabulated by electoral ballot. So it isn't how the candidates do on a national basis that matters, it's how many and which states they win. To know how big an obstacle high unemployment poses for the President Obama in 2012, you need to think about each state on a case-by-case basis.

We can know a few things with a fair amount of certainty. There are some states that lean so heavily left that President Obama would have had to make the economic situation much, much worse for there to be any chance he loses them. That leaves the states where his win margin was smaller. For those states, if any have been disproportionately affected by the bad economy, then they could hurt President Obama's re-election chances.

This was the topic of a Wall Street Journal article on Monday, which highlighted Florida, Michigan, North Carolina, and Nevada. They all have high unemployment rates and are considered swing states. I thought the analysis might be more interesting if expanded to all states and if the change in unemployment rate was taken into account. After all, if a state's unemployment rate fell from 10.6% to 10.2% (see Michigan), then residents might not be as angry as they would be if their rate had risen from 7.1% to 9.3% over the same period (see New Jersey).

Here's the chart (click to enlarge):

states unemployment obama 2011-04 v5.png

A few things to note. First, I color-coded the change column to show severity. In that column, red indicates that unemployment rose by at least 2.0%, orange indicates that unemployment rose but by less than 2.0%, and green indicates no rise or a decline. There isn't a lot of green.

The margin column provides some indication of the states that are a sure-thing for President Obama. If he won a state by more than 20 points, then they tend to lean pretty firmly to the left. They're highlighted dark blue, while states he won by 20% or less are highlighted light blue. States he lost are highlighted red.

Finally, just for a qualitative explanation of where President Obama might run into trouble, I tracked the states where he won by less than 20% of the vote and where the unemployment rate has risen by at least 2%. As you can see, there actually aren't that many states that fit these criteria. Their electors add up to 72. Based on the 2008 results, that would still make for an Obama win by 48 points. But if you assume that a 1% increase in unemployment per swing state is enough to change voters' minds, then 104 electors would change hands, and Obama would lose by 16 points.

Of course, this is all hypothetical and the unemployment statistics that really matter are those for November 2012. But this begins to explain where President Obama will face the biggest challenges. Expect him to spend a lot of time campaigning in Florida and New Jersey in 2012.

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