PRINCETON, NJ -- The political composition of U.S. adults held fairly steady in 2010 compared with 2009. Conservatives remained the largest group, followed by moderates and then liberals. At 35%, the percentage of moderates has declined to a new low, highlighting the increased political polarization that has occurred over the past decade.

Gallup measures Americans' political ideology by asking respondents to define their views as very conservative, conservative, moderate, liberal, or very liberal. The trends represent annual averages of stand-alone, multiday Gallup surveys conducted each year, with more than 26,000 interviews in the 2010 data set.

In 2010, as in prior years, relatively few Americans described themselves as either very conservative (10%) or very liberal (6%). The vast majority of Americans favor the more temperate political labels.





Fewer people in all three party groups call themselves moderate today than did so in 2002, but the decline is particularly steep among Republicans. The percentage of Republicans calling themselves moderate fell from 31% in 2002 to 27% by 2006, and now stands at 23%. There has been a commensurate increase in the percentage of Republicans calling themselves conservative, now at a record-high 72%.





Among Democrats, Gallup trends document declines in the proportion of moderates as well as conservatives. At the same time, the percentage of Democrats identifying as liberal has climbed from 29% in 2000 to a record-high 40% today.





The ideological orientation of independents was fairly steady from 2000 through 2008, but since 2009, their views have followed the same path as Republicans', becoming less moderate and more conservative. Still, the slight plurality of independents remain moderate.





Conservatism in 2010 Peaked in Second Quarter

Although the percentage of conservatives among U.S. adults averaged 40% in 2010, it varied slightly during the year, peaking at 42% in the second quarter (after a 41% reading in the first quarter), in the first few months after passage of the landmark healthcare reform act. The conservative ID subsequently fell to 40% and 39% in the third and fourth quarters, and will bear watching in 2011.

Bottom Line

While the political pendulum in Washington can swing widely, Americans' political ideology, like their party identification, tends to shift more gradually. Such a shift has been underway in recent years. While the changes are not large, they are unmistakable. Moderates are growing fewer in number while the percentages of conservatives and liberals have expanded. Conservatism has gained ground among Republicans and independents, while the growth in liberalism is strictly among Democrats.