What explains President Barack Obama's nine-point drop in voter approval in today's New York Times/CBS News poll? First, it's not a total aberration. While Gallup has the president doing better, a Washington Post/ABC News poll published this week also has bad news for the president, with 59 percent of voters rating Obama negatively on the economy and his overall approval rating dropping to 46 percent, from 50 percent in the last Post/ABC poll.
The consensus, captured by the Post's Dan Balz and Jon Cohen, seems to be that "gas prices are the main culprit" for the decline.
Republican consultant Mike Murphy has a more nuanced take:
"I think the President suffers from a lack of public confidence in his economic leadership," Murphy said in an email. "Any bad economic news, in this case soaring gas prices, triggers a fast decline in his numbers. He lacks any reserve of support on economic issues to fall back on. This is a definite sign of political vulnerability."
Ed Rollins, another Republican consultant, cites gas prices combined with a decline in "Republican bickering" in the news about the primary election.
As Nate Silver of the Times notes, polls are subject to statistical noise. They're also subject to the vagaries of the voters themselves, whose answers to poll questions may not always mean precisely what they say. For example, in the latest Bloomberg News poll, many more whites say their personal situation has deteriorated than improved under Obama's presidency -- 42 percent to 30 percent. Yet among non-whites, 55 percent say they are better off today and only 23 percent say their situation is worse.
Is that true? Not statistically. Unemployment for whites, blacks and Hispanics was higher last month than in January 2009, when Obama took office. The recession has generally been much harder on blacks and Hispanics than whites, wiping out much of black and Hispanic America's household wealth.
Context -- and the human capacity to rationalize -- is difficult to measure. Some whites who don't like Obama undoubtedly won't give him credit no matter what the economy does. Likewise, some black voters may be saying their personal situation is better when, in purely economic terms, it really isn't.
The price of gas doesn't begin to account for such views. It's worth noting that approval of Obama's handling of foreign affairs also declined in the Times and Post polls without the benefit of a ready explanation.
"People have been through so much since 2008 that anything shakes them up," says former Democratic consultant Bob Shrum. "If jobs keep going up, Obama will do better."
The history of presidential politics suggests that's true -- though what voters will tell themselves about it is anybody's guess.
(Francis Wilkinson is a member of the Bloomberg View editorial board. Follow him on Twitter.)