For all you bed-wetters out there worried about more republican voters registering than democrat voters check out this podcast
http://www.politico.com/story/2016/08/nerdcast-2016-the-rise-of-the-alt-right-227440
and go to the 35:55 mark
Basically, the guys point is that registration trends in the Eastern half of the United States somewhat reflect the time before the Republican Southern Strategy.
When we see new republican registration we are likely not seeing new Republican voters, but just new Republican primary voters who wanted to vote for Trump.
This is also born out by trends in the Western states. Republican registered voters aren't leading democrats, likely because the Southern Strategy didnt impact these states.