10/30/2008 - The Democratic Party has substantially widened its margin in party identification over the Republican Party since the last presidential election and has made notable gains in many of this year's political battleground states.
Nearly four-in-ten voters (38%) identified themselves as Democrats in 2008 surveys by the Pew Research Center; 34% self-identified as independents; and 28% identified themselves as Republicans. These data are based on more than 28,000 interviews conducted this year by the Pew Research Center.
In 2004, the balance of party affiliation was far more closely divided: 35% of voters called themselves Democrats, 33% Republicans, and 32% independents.
View the charts and the complete commentary Democrats Hold Party ID Edge Across Political Battleground on the Pew Research Center Web site.