PRINCETON, NJ -- Hawaii shows the largest advantage for the Democratic Party over the Republican Party among U.S. states, along with the District of Columbia, in the first half of 2011. The most Republican state is Utah.

The results are based on interviews with more than 170,000 U.S. adults as part of Gallup Daily tracking from January through June, including 1,000 or more adults in 41 states. Each state's data are weighted to be demographically representative of that state's adult population.

Nationwide, Democrats had a slight advantage in the first half of 2011 in the Gallup tracking data, with 44% of Americans identifying as or leaning Democratic and 40% identifying as or leaning Republican.

Gallup classifies states as being more Democratic, or more Republican, based on the difference between the percentage of state residents who identify as or lean Democratic and the percentage who identify as or lean Republican.

These figures take the partisan leanings of independents into account. This gives a truer sense of the relative strength of each party in a state, given wide disparities in the percentage of political independents. These range from lows of 30% independent identification in the District of Columbia and 31% in Pennsylvania to highs of 60% in Rhode Island and 59% in Alaska. Many states with high proportions of independents are dominated by one party electorally.

The most Democratic states are concentrated largely on the East coast -- among the top 10, only Hawaii and Illinois are not located in New England or the Mid-Atlantic region. The four most Republican states are in the West, with 5 of the top 10 coming from that region. The patterns for party affiliation by region are similar to what Gallup finds for presidential job approval.

The most balanced states politically in the first half of 2011 were Virginia and Mississippi (both are evenly divided between Republicans and Democrats), Colorado (with a one-percentage-point Republican advantage), Missouri, Arizona, and Arkansas (with two-point Republican advantages), and Georgia (with a two-point Democratic advantage).

The party affiliation estimates are based on the entire state adult population, and do not necessarily reflect each party's electoral strength within a state. A state's voting electorate may be tilted slightly more to one party than the basic affiliation figures due to differences in turnout between Republicans and Democrats in the state and perhaps the strength of the respective party organizations in the state.

The full results for each state are shown on page 2.

Party Affiliation Largely Stable in 2011

Gallup earlier this year documented significant shifts in party affiliation at the national and state levels since President Barack Obama took office. But the political environment appeared to stabilize between 2010 and the first half of 2011, with essentially no change in party affiliation at the national level, and little meaningful variation in the states.

North Dakota and Louisiana are two states that did show meaningful change in party affiliation during the first half of 2011. North Dakota shifted from a slight Republican advantage of 3 points in 2010 to a more substantial 18-point Republican lead in 2011. Louisiana moved from a 3-point Democratic advantage last year to a 6-point Republican advantage thus far in 2011.

But those states were the exceptions. Nine of the most Democratic states in 2010 are also among the top 10 in the first half of 2011, with California dropping out and Illinois entering. Eight of the top 10 Republican states are the same between the two time periods, with New Hampshire and South Dakota falling out of the top 10, and North Dakota and South Carolina moving in.

Implications

The first half of 2011 looked a lot like 2010 politically in the United States, with Democrats enjoying a slight advantage in party affiliation nationally. The president's approval rating between the two time periods was also stable.

But that stability may not continue in the second half of 2011, with President Obama's approval rating slipping to 44% in July and further to 41% thus far in August as the nation struggles with the national debt and weak economy.

Whether those trends continue and affect the way Americans align themselves with the political parties, and how that positions the parties heading into the 2012 elections, will become clearer in the coming months.

This story is part of a series of midyear updates on Gallup's State of the States data, to be released in August on Gallup.com. Gallup.com will report new full-year totals in early 2012 based on all 2011 surveys.