This news release – announcing that there are now roughly 20,000 more registered Republicans in Iowa than registered Democrats – suggests that Hawkeye state Republicans can crow about a dramatic turnaround, pointing out that back in January 2009, Iowa Democrats enjoyed a 110,000 voter registration advantage.

In terms of how many voters are registered with each major party, Democrats continue to hold advantages in several key swing states, but in all of those states, their advantage is considerably smaller than it was in 2008.

In Florida, as of last month there are 4,627,929 registered Democrats and 4,173,177 registered Republicans, which amounts to a a 454,752-voter advantage for Democrats. (Keep in mind, Florida has 11.5 million registered voters, so there are a lot of unaffiliated and third-party voters.)

In 2008, there were 4,800,890 registered Democrats in Florida and only 4,106,743 registered Republicans, a 694,147-voter advantage. So while the number of voters who registered with the GOP is up from four years ago, Democrats are down roughly 170,000.

In Nevada, there are 447,881 registered Democrats to 400,310 registered Republicans, a split of roughly 47,000. (Keep in mind, the state has 1.4 million registered voters right now.) In 2008, the state split 531,317 registered Democrats to 430,594 registered Republicans, a split of roughly 100,000.

In New Mexico, as of July 31, there are 582,656 registered Democrats to 385,898 registered Republicans, a Democrat advantage of 196,758 voters. In 2008, there were 594,229 registered Democrats and 375,619 registered Republicans, an advantage of 218,610 voters.