(CNN) -- Nearly two-thirds of Americans surveyed consider Iraq to be in a civil war, a CNN poll said Thursday, and more people view the three major architects of the U.S.-led operation there unfavorably than favorably.

Iraq, particularly its capital, Baghdad, has endured months of Sunni-Shiite sectarian killings, and debate has simmered over whether the country has or has not entered into a full-blown or low-grade civil war.

Asked whether Iraq is "currently engaged in a civil war," 65 percent of the poll's respondents said "yes," and 29 percent answered "no." By comparison, a Los Angeles Times/Bloomberg poll in April found 56 percent of the respondents believed Iraq was in a civil war, while 33 percent disagreed.

The poll found that most Americans polled -- 60 percent -- said they have a clear idea of what the United States is fighting for in Iraq, while 39 percent said they did not.

The same question was posed 39 years ago, when America was deeply divided over Vietnam. At the time, 49 percent said they had a clear idea of what the United States was fighting for there; 48 percent said no.

Of those questioned now, more people -- 48 percent of those surveyed -- considered themselves doves than hawks (44 percent). When the Iraq war began, the numbers were not that much different: 45 percent of those polled considered themselves doves, while 43 percent called themselves hawks.

The poll defined a hawk as "someone who believes that military force should be used frequently to promote U.S. policy" and a dove as "someone who believes the U.S. should rarely or never use military force."

The poll's results came a day after a separate poll by the University of Maryland found that 71 percent of Iraqis favor a commitment by U.S.-led forces in Iraq to withdraw in a year. (Details)

As for the nation's leaders, half or more of the respondents of the CNN poll expressed unfavorable views toward President Bush, Vice President Dick Cheney and Defense Secretary Donald Rumsfeld.

The new poll found that 50 percent of those surveyed held an unfavorable view of Rumsfeld, while 35 percent held a favorable view. The poll found a five percentage point rise in his unpopularity since April. (Graphic: Rumsfeld approval rating)

By contrast, Rumsfeld's popularity was riding high in February 2003 as preparations were under way for the war in Iraq: 58 percent had a favorable view of him, while 20 percent did not.

Bush's popularity has risen since April, when 57 percent of those surveyed viewed him unfavorably, and 40 percent favorably. The latest poll found that 52 percent had an unfavorable view of him, while 46 percent saw him favorably.

As for Cheney, 37 percent have a favorable view of him, compared with 57 percent who do not. In April, 35 percent saw him favorably, while 52 percent did not.

In contrast, first lady Laura Bush and Secretary of State Condoleezza Rice emerged popular. The poll said 68 percent have a favorable opinion of the first lady, while 23 percent have an unfavorable opinion of her.

Rice's numbers are 57 percent favorable and 30 percent unfavorable -- the same favorable rating as in April, but she had a lower unfavorable rating -- 22 percent -- at that time.

The Opinion Research Corporation conducted the poll by surveying 1,009 adult Americans by telephone Friday through Sunday. The poll has a sampling error of plus or minus 3 percentage points.

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