There may be some explanation for the precipitous drop in Democrat registration but it cannot be a good sign for meeting the 2008 turnout models. 

Voter registration in the Buckeye State is down by 490,000 people from
four years ago. Of that reduction, 44 percent is in Cleveland and
surrounding Cuyahoga County, where Democrats outnumber Republicans more
than two to one.  An August study by the left-leaning think tank Third Way showed that the
Democratic voter registration decline in eight key swing states
outnumbered the Republican decline by a 10-to-one ratio. In Florida,
Democratic registration is down 4.9 percent, in Iowa down 9.5 percent.
And in New Hampshire, it’s down down 19.7 percent.

There may be some explanation for the precipitous drop in Democrat registration but it cannot be a good sign for meeting the 2008 turnout models. 

Voter registration in the Buckeye State is down by 490,000 people from
four years ago. Of that reduction, 44 percent is in Cleveland and
surrounding Cuyahoga County, where Democrats outnumber Republicans more
than two to one.  An August study by the left-leaning think tank Third Way showed that the
Democratic voter registration decline in eight key swing states
outnumbered the Republican decline by a 10-to-one ratio. In Florida,
Democratic registration is down 4.9 percent, in Iowa down 9.5 percent.
And in New Hampshire, it’s down down 19.7 percent.