The Boston Globe reports that Democratic numbers for newly registered voters in swing states are down considerably:
Democratic rolls increased by only 39,580, less than one-tenth the amount at the comparable point in the 2008 election. At the same time, GOP registration has jumped by 145,085, or more than double for the same time four years ago. Independent registration has shown an even stronger surge, to 229,500, almost three times the number at this point in 2008.
Philip Bump doesn't think registration is a huge indicator for turnout:
[V]oter registration is almost always a mid-summer time-kill meant to keep volunteers engaged and to provide a metric to the press. Newly registered voters — except when the registration is same-day — are far less likely to vote. Far less. It's not a turnout strategy, it's an energy strategy.
Relatedly, Sasha Issenberg studies increasingly sophisticated registration by mail tactics.
(Photo: Volunteers for the Obama 2012 campaign leave fliers on residences as they canvass for votes in South Tampa, Fl. By Angel E. Valentin/For The Washington Post via Getty Images.)