As I mentioned in my last post, the forecasters and the media don't care how the congressional races actually went on June 5. They've accepted the idea that all Democrats will do better and make their races competitive. That idea is ludicrous. No matter how strong past evidence, there has always been some that go the other way or the change is very small.
In the 2010 CA-3 primary race Ami Bera "lost" by 18.6 points. He only lost by 6.9 in the general. So he closed by 11.7 points, exactly what he'd need this time.
In 2008 Lungren won by 15 points in the primary and 5.5 in the general. In 2006, however, Lungren actually went from a 14.9 point primary win to 21.6 in the general.
So 11.7 is possible and it's likely that some Democrats will do better than 11.7 points. I do, however, see around a 6 point average change. That's less than 2010, but more than 2006 or 2008. In each year the exit polls were around 1 point more Republican than registration. On a normal bell shaped statistical curve an 11.7 point improvement would be at the high end and won't happen in more than a handful of races.
This district is entirely in Sacramento county. Sacramento county is 43%D/33%R. It was 46%D/38%R in the primary. If the county is 43%D/33%R in the general, it's not guaranteed Bera will even do better. He'll be relying more heavily on independents than he did then.
The district is 39%D/39%R. I'm still waiting final numbers, but it was probably around 42%D/44%R in the primary. If a 2% participation advantage produces a 12 point win for Lungren then Bera will need an 8-10% participation advantage to win in November. He'd have to count heavily depressed turn-out that'd make 2008 look like a good Republican year. That's 2008 in Illinois, not 2008 in California, which wasn't nearly as bad for Republicans as it was elsewhere.
Republicans have been nearly as energized as they were in 2010. So I don't know what's going to keep them home. Bera would have to hope that independents, who appear to have voted heavily Lungren in the primary, flip to him. Again, not likely.
Of course the participation numbers I've seen could be wrong. Maybe Republican turn-out was more elevated than it looks. Chances are, however, it isn't. Those big shifts are likely to come in Southern California districts where there was a large disparity between registration and turn-out. Right now I see Lungren coasting to a 55%-45% win.