Since the 2012 election there are 986,557 less registered voters in California. That would be alarming if there were actually 986,557 less voters in California. There aren't. There are that many non-voters no longer on the rolls. Actually there are some new voters, so the number of non-voters culled is higher than that. When counties delete non-voters from the rolls it looks like they're doing something but they are, in fact, just removing a name of someone who has moved or died who shouldn't be on the list.
There are 589,349 less Republican voters and 527,767 less Democratic voters. That’d appear to favor Democrats but eliminating more Republican non-voters from the rolls doesn’t mean that more Democratic voters shouldn’t have been removed from the rolls. In fact, the four counties that eliminated the most voters are 36.4% Republican and 34.4% Democratic. If every county was eliminating non-voters using the same criteria and with the same thoroughness we'd see a much higher Democratic number than that. Of course, there are more Democratic registrants. So there should be more Democratic non-voters.
Republicans have a much higher voting rate in June than Democrats and a slightly higher voting rate than Democrats in November. People have assumed that Republicans are just more likely to vote. I'm sure that's part of it, but what if another part is that the Democratic voting rate looks lower because there are more ghost Democrats on the rolls than ghost Republicans? Los Angeles County, home to almost a third of Democratic voters, has actually increased their voter rolls since November 2012. I'm speculating here, but I'd bet the LA county registrar doesn't do a diligent registration list purge. Maybe LA county's voting rate isn't nearly as low as people think. There are just more non-voters on the rolls. The Secretary of State should put out numbers listing what parties new registrants and what parties party switchers register with. Those are real voters. I'm speculating here but I suspect those numbers would favor Democrats. Unless we get those numbers there's no way to know. This June a higher percentage of Republican voters will vote than Democratic voters. But will they really?