PRINCETON, NJ -- An average of 47% of Americans identified as Democrats or said they were independents who leaned Democratic in 2012, compared with 42% who identified as or leaned Republican. That re-establishes a Democratic edge in party affiliation after the two parties were essentially tied in 2010 and 2011.

The estimates are based on an aggregate of all 2012 Gallup and USA Today/Gallup polls, consisting of more than 20,000 interviews.

Gallup has measured party identification and leaning consistently since 1991. During that time, Democrats have usually held an advantage, including the high margin of 12 points in 2008, the year President Barack Obama was elected. Republicans have held an advantage in only one year -- 1991, when President George H.W. Bush enjoyed record-high approval ratings after the Persian Gulf War. The two parties were essentially tied in 1994-1995, 2001-2003, and 2010-2011.

In 2012, 31% of Americans identified as Democrats, with an additional 16% initially saying they were independent but when asked if they leaned toward either party, they said Democratic. Meanwhile, 28% of Americans identified as Republicans, with another 14% leaning toward the GOP.

The percentages of Republican and Democratic identifiers were essentially unchanged from 2011 to 2012. The new Democratic advantage is mostly due to an increased proportion of Democratic-leaning independents and a decreased proportion of Republican-leaning independents. Thus, the movement comes almost exclusively among Americans with weaker attachments to the political parties.

Americans last year continued their trend toward greater political independence. The 40% who initially identified as political independents matched the record high from 2011. That is particularly notable, given that the usual pattern is for the percentage of Americans identifying as independents to decline in a presidential election year. In each of the last four presidential election years, dating back to 1996, the percentage of independents was lower than in the year prior to the election.

The increase in political independence has led to a reduction in Democratic and Republican identifiers, with the percentage of core Democrats and Republicans currently in the lower range for the past 25 years. In fact, 2012 marked the sixth consecutive year that less than 30% of Americans identified as Republicans. This includes 2010, when Republicans made huge gains in the midterm congressional elections.

Implications

The year 2012 saw President Obama re-elected to office and saw Democrats regain an advantage in party affiliation among the American public. But that bit of good news for the Democrats is tempered by the fact that a record number of Americans continue to claim political independence, at least when initially asked to say which party they support.

The rise in independence is perhaps not surprising, given the low esteem in which Americans hold the federal government and the political parties. But with most Americans willing to at least express a leaning to either party, it does suggest the potential for the parties to gain more solid adherents in the future.