Last month’s sample was questionable. This month’s sample is terrible:

The 2008 national exit poll sample, taken when Hopenchange fever was at its zenith, was 39D/32R/29I, or D+7. This one, after three years of Obamanomics dreck, is somehow D+11 if you include leaners and D+12(!) if you don’t. Anyone feel like taking these results seriously?

And yet we soldier on, my friends, reminding ourselves at every step that lame content is still content. One interesting takeaway: The attacks on Bain are driving Obama’s favorables down too, even with a very Democratic sample.

[T]he percentages signaling a less favorable impression about these candidates – especially at this point in the race – are greater than what the NBC/WSJ poll showed in the 2004 and 2008 presidential contests.

“This is not characteristic … for July,” says Republican pollster Bill McInturff, who conducted this survey with Democratic pollster Peter D. Hart. “These are numbers you usually see in October.”…

The president’s favorable/unfavorable score in the poll is 49 percent to 43 percent, a slight change from June when it was 47 percent to 38 percent.

Moreover, 33 percent view Obama very positively, while 32 percent view him very negatively – which is his highest “very negative” number in poll.

By comparison, Romney’s overall favorable/unfavorable score is 35 percent to 40 percent, with 24 percent viewing him “very” negatively – also his highest mark here.

In fact, Romney would be the first GOP presumptive presidential nominee since 1996 to head into his nominating convention with a net-negative favorable/unfavorable score.

Only once before has Obama been as high as 30 percent when people were asked if they viewed him “very negatively.” This month he’s at 32 even though NBC’s respondents are heavily blue. He still leads overall, 49/43 among registered voters and 49/41 in battleground states, but Romney leads by two points among voters who are “high interest.” The Bain attacks haven’t done much to tilt people’s opinion about Bain either: In May, the favorable/unfavorable split for the firm was 9/19 whereas this month it’s 12/23. And yes, Obama’s earning himself a reputation as a negative campaigner:

Romney’s lead on the economy is increasing, too, as pessimism about a recovery deepens. The first column in the first table here is O, the second is Mitt:

So what explains Obama’s lead (besides the help he’s getting from the sample, natch)? Three things, I think. One: He still leads on likability, although some polls say he leads big and others say his lead is more modest. His favorable rating here is 49/43 compared to 35/40 for Romney, which is interesting insofar as his negatives are now actually higher than Mitt’s. See why he’s putting out those warm let’s-you-and-I-chat ads? Two: O leads on virtually every issue and leadership metric except the economy. Maybe that’s a simple function of voters not having sized Romney up yet, but it could be that by investing his entire campaign in building an economic edge, Mitt’s more or less abandoned the field on lesser issues. Three: Just because the Bain attacks aren’t doing much damage doesn’t mean all of O’s attacks are fizzling.

The fact that Obama’s now running positive ads makes me think he’s concluded that, for the moment, the attacks on Romney are hurting him more than they are Mitt. But I wonder if that’ll change if he can build up enough of a lead in likability. Obama won’t mind seeing his favorables turn negative, I assume, as long as Romney’s are turning at least as negative in the process. Something to look forward to in September and October!