Interesting study by Bloomberg that shows the Democrats lost around 480,000 members in swing states since 2008 while indpendents increased by about 440,000.
The GOP picked up 38,000 members.
The collective total of independents grew by about 443,000 in Colorado, Florida, Iowa, Nevada, New Hampshire and North Carolina since the 2008 election, according to data compiled by Bloomberg from state election officials.
During the same time, Democrats saw a net decline of about 480,000 in those six states, while Republicans -- boosted in part by a competitive primary earlier this year -- added roughly 38,000 voters in them, the analysis shows.
"Democrats hit the high-water mark for registration in 2008, so it's natural that they are going to see some drop off," said Michelle Diggles, a senior policy analyst with the Democratic-leaning Third Way research group in Washington who conducted a similar study earlier this year.
The rise of independent voters has had a major impact on recent election results.
In 2008, President Barack Obama won 52 percent of the independent vote, according to national exit polls, which was one percentage less than his overall total. Senator John McCain of Arizona, his Republican opponent, collected 44 percent of the independent vote -- 2 points less than his overall total. Independents represented 29 percent of the total electorate that year.
In 2006, independents backed Democrats by an 18-percentage- point margin nationwide in House races, handing the party control of the chamber for the first time in 12 years. In 2010, they backed Republicans over Democrats in House races by a 19- point margin, as Republicans regained the chamber's majority.
Independents are far more centrist than either Democrats or Republicans, but a good number of them lean right more often. They are there for the taking - along with the election - if Romney can tap into the dissatisfaction of those former Dems.