To see how unusual it is for the GOP to lead in this metric, scroll through RCP’s compilation of generic-ballot polling for 2013. Before this month, only once all year had Republicans topped Democrats in a poll taken by someone other than Rasmussen. Even Rasmussen (which asks this question every week) has found the Dems ahead far more often than not. Suddenly, in the last three weeks, Quinnipiac shows the parties tied and both Fox News and now CNN show the GOP with a small lead. As does Rasmussen, of course.

I wonder why.

Democrats a month ago held a 50%-42% advantage among registered voters in a generic ballot, which asked respondents to choose between a Democrat or Republican in their congressional district without identifying the candidates… But the Democratic lead has disappeared. A new CNN/ORC poll indicates the GOP now holds a 49%-47% edge… “It looks like the biggest shifts toward the Republicans came among white voters, higher-income Americans, and people who live in rural areas, while Democrats have gained strength in the past month among some of their natural constituencies, such as non-white voters and lower-income Americans,” said CNN Polling Director Keating Holland. “If those patterns persist into 2014, it may indicate that Obamacare is popular among those who it was designed to help the most, but unpopular among the larger group of voters who are personally less concerned about health insurance and health care,” Holland said.

If you’re going to launch a new redistributionist program to benefit your core constituencies, you need to be careful to obscure where the money’s coming from. If it’s too clear who the “winners” and “losers” are, then you’ve got three big electoral problems potentially: (1) the losers might outnumber the winners; (2) even if the winners outnumber the losers, the losers will likely be more motivated to vote — an especially dangerous problem for O given that his main beneficiaries here, the poor, typically vote at a lower rate to begin with; and (3) if the losers are easily identified, the PR opportunities for opponents are limitless. As Matt Lewis said yesterday, one of the ironies of the ObamaCare rollout is that the sob stories are all on the side of the opposition right now. That’s a big part of why CNN’s numbers are what they are.

By the way, last month’s eight-point generic-ballot for the GOP was unusually steep, thanks of course to the shutdown. Typically they trail on the GB by three or four points but the backlash to the government being closed down pushed them lower. The real significance of today’s data is that the O-Care debacle has completely erased the advantage Democrats were hoping that the shutdown would give them. It’s come to this:

Race-by-race polling conducted over the last month has painted a grim picture of the difficult environment Senate Democrats are facing next year. In Louisiana, a new state survey showed Landrieu’s approval rating is now underwater; she tallied only 41 percent of the vote against her GOP opposition. In Arkansas, where advertising on the health care law began early, Sen. Mark Pryor’s approval sank to 33 percent, a drop of 18 points since last year. A new Quinnipiac survey showed Sen. Mark Udall of Colorado, who looked like a lock for reelection last month, in a dead heat against little-known GOP opponents. Even a Democratic automated poll from Public Policy Polling showed Sen. Kay Hagan of North Carolina running neck-and-neck against Republican opposition, with her job disapproval spiking over the last two months. These are the types of numbers that wave elections are made of… “You want to prevent your race from being about Obamacare. If you enable your race to be about Obamacare, you’re making a mistake,” said Democratic pollster Mark Mellman, who’s working for Landrieu. “You need to explain what you’re trying to fix, and you better be trying to fix something. If there’s nothing you want to fix, there’s something wrong with you. At this point, it’s hard to defend the benefits, but you can say we’re not going back to the evils of the old system.”

Said another Democratic strategist of Obama’s collapsing job approval, “This is serious. This is much more serious than I hear some Democrats saying publicly. This is not a temporary drop.” Indeed: Not only is it unusual for a president’s approval rating to rebound significantly deep into his second term, it’d be especially unusual for it to happen to O given all the logistical challenges that ObamaCare faces next year. The loser/winner dynamic I described above will only get worse once small businesses start dumping employees onto the exchanges. Which is why, I think, you’re seeing Senate Democrats begin to propose fixes just six weeks in: They know it’ll get worse. If you want to be reelected, the time to start distancing yourself from O-Care is yesterday.

One other interesting wrinkle to all this. The CNN data inspired me to look at three metrics on RCP — Obama’s job approval, public support for ObamaCare, and of course the generic ballot. Here’s what Obama’s approval rating looks like since October 1st. He remains more or less flat throughout October, no doubt helped by public anger towards the GOP over the shutdown, but then he starts a slow, steady decline in November:

Oddly, those trend lines don’t really match what happened to ObamaCare itself. Support for the law remains more or less constant into November and then, around November 10th, the lines start to diverge:

The generic ballot looks more like the ObamaCare trends than O’s job approval. You see a big Democratic lead in the wake of the shutdown and then the bottom drops out on — ta da — November 10th:

Question: What’s going on with November 10th? Is that just some delayed reaction to Obama’s cratering approval rating or did something specific happen that I’m forgetting?

While you mull that, here’s Kay Hagan concluding that this is all the insurance companies’ fault or something.