Here’s a new report by Third Way.  They find that in 5 of 8 battleground states that register voters by political party, the number of registered independents is up.  In 7 of 8 states the number of registered Democrats is down.  The GOP is down in 6 of those 8.  They then write:

Beyond these battleground states, national surveys such as the American National Election Studies and Pew show a steady increase in Independent self-identification throughout the United States. According to Pew, between 2000 and 2011, both the Democratic and Republican parties lost members, and the number of self-identified Independents increased by 8%. In 2000, 33% of the electorate identified as a Democrat, 28% as a Republican, and 29% as an Independent.  By 2011 only 32% identified as a Democrat, 25% as a Republican, and 37% as an Independent. Democratic and Republican losses were mirrored by gains in Independents…