At TNR yesterday, Nate Cohn looked at Pew’s latest measurement of presidential approval ratings–one of several to show a significant mid-summer decline–and saw a very clear trend:

Today’s Pew Research poll paints a clear picture of the Obama defectors. They’re almost exclusively white voters without a college degree. Obama’s standing among minorities, college educated whites, and affluent whites has actually improved since the final Pew Research poll before last November’s presidential election. Instead, Obama’s support among white working-class voters has taken a huge hit, opening an unprecedented 41 point education gap among white voters. Incredibly, the poll now even shows Obama with a stronger approval rating among affluent whites than downscale whites—something that’s never happened for a Democrat in a presidential election.

The source of the collapse isn’t clear, but Obama’s resilience with minorities and well-educated voters is consistent with the possibility that cultural issues like immigration, gun control, and Trayvon are driving the shifts in the president’s numbers.

More alarmingly for Democrats, the most recent drop in Obama’s white-working-class job approval numbers is not in the South, but nearly everywhere else: as compared to the November 2012 Pew survey, it’s down 22 points in the Northeast, 16 points in the West, and fourteen points in the Midwest, but just 3 points in the South, where Obama’s WWC problem has probably reached the point of diminishing returns. Nate figures the Midwest is the ripest GOP opportunity. But he also warns that focusing exclusively on the WWC demographic is risky, since many of these voters are still self-identified Democrats who are always going to be open to a return to their ancestral allegiance.

So the real problem for the GOP remains: how in an ideologically inflexible party can Republicans advance messages and candidacies that expand their own coalition? Sagging approval ratings for Obama are not the same thing as bankable votes for the GOP, particularly when you look ahead to 2016, when Obama will not be on the ballot.

While Pew has released the breakouts Nate cites for presidential approval ratings from their July polling, the firm hasn’t done so yet for other important optics, including approval ratings for the two parties, which have generally been sinking right along with Obama’s. It will be interesting to see if the WWC disgruntlement with Obama has or had not fed any improved perceptions in this demographic for the Republican Party.

Ed Kilgore

Ed Kilgore is a political columnist for New York and managing editor at the Democratic Strategist website. He was a contributing writer at the Washington Monthly from January 2012 until November 2015, and was the principal contributor to the Political Animal blog.