A lot of people casually throw out there "All the Republicans are re-registering Independent." So we looked. 1/4
With over 40,000 surveys completed in 2016 Primary we can see that there was a good amount of re-registration, and, yes, of the 12,749 Republicans, 300 became Democrats and 830 became Independent/Other. That's a 91.4% retention rate for Republicans, or about 9% switching. 2/4
But, among Democrats we also saw among the 20,792 surveyed in the 2016 Primary, 1,302 became Ind/Other and 243 became Republicans. That's a 92.6% retention, or 7.5% switching. 3/4
So, in summary, not that many voters are re-registering to switch parties. A 9% here and 7.5% there isn't a massive realignment. The shifting in partisanship isn't from voters who are changing parties, it is from the dramatic change in partisan registrations among new voters. 4/4 
Bonus: Not any difference by Gender....
Bonus #2 - a bit more leaky among younger voters.
Bonus #3 - no African Americans are switching from Dem to Rep. But 93% of Rep Latinos aren't switching.
Bonus #4 - Only 76% of the Republican John Kasich voters are still Republicans. That's actually the biggest shift we can find.
Bonus #5 - income doesn't seem to matter.
