One reason to doubt these numbers, however, is that many of these districts that look bad for the GOP are in Orange County. That isn't shown in the BVM returns. In the 2014 primary Orange County VBM returns were R+18. They are R+10 here. While that looks like a big change, it's actually the average change for the state. Since the exit polls aren't showing disaster elsewhere for the GOP, just the party doing a bit worse, it's possible there's a glitch in the OC numbers.
Take Darrell Issa's CA-49, for example. VBMs were R+17 two years ago and Issa won the primary by 24% over the two Democrats combined. This year they are R+8. I'd expect a 9 point drop and Issa to be 15 points ahead. Instead he's up by 0.3%. I find it hard to believe that Jeff Denham is coasting to an 18 point win, but Issa is running even. Yes, I'm skeptical but the results will tell us whether that skepticism is warranted. That's what makes it fun.