The broad relationship between knowledge and sentiment, however, is positive. Overall, people who feel they understand Islam, or who have a Muslim friend, are 22 points more apt to view the religion favorably and 17 points more apt to see it as peaceful, compared with those who lack a basic understanding or a friend who's Muslim.
There are political and ideological differences here as well. About two-thirds of liberals and moderates see Islam as peaceful, as do 62 percent of Democrats and independents; fewer conservatives or Republicans agree, 49 percent and 51 percent respectively. And just 26 percent of conservatives and 33 percent of Republicans see the religion favorably.
Islam also is more apt to be seen unfavorably by less-educated adults, Southerners and senior citizens than by their counterparts.
CHANGES -- There have been notable changes in some of these groups. Compared with the first ABC poll to ask the question in October 2001, unfavorable views of Islam have increased by 23 points among senior citizens, 19 points among conservatives, 18 points among Republicans and 12 points among Southerners.
There's one group -- liberals -- among whom unfavorable views of Islam have declined, by 11 points.
METHODOLOGY – This ABC News/Washington Post poll was conducted by telephone March 26-29, 2009, among a random national sample of 1,000 adults including both landline and cell-phone-only respondents. Results for the full sample have a 3-point error margin; click here for a detailed description of sampling error. Sampling, data collection and tabulation by TNS of Horsham, PA.