Among Republicans, 63 percent gave clergy one of the two top ratings for ethics, compared with 40 percent of Democrats.
In a piece accompanying the poll earlier this month, Gallup Senior Editor Jeffrey M. Jones wrote that Republicans might think more highly of clergy, police and military officers "because those people work in traditional institutions in American society, which Republicans may hold in greater esteem because of their generally conservative ideology."
"Greater religiosity among Republicans than among Democrats also factors in to Republicans' higher ratings of clergy," Jones added.
Young people aged 29-34 tend to rate professionals more highly than those 55 and older, but the pattern does not hold for clergy. Less than 1 in 3 young people (32 percent) give clergy high moral marks, compared with 50 percent of those 55 and older.
This may be because young people tend to be less religious than older people, Jones writes.
This year, clergy took a back seat to nurses, pharmacists, schoolteachers, medical doctors, military and police officers.
Nurses are the most trusted and have been nearly every year since Gallup added them to the poll in 1999, with 82 percent of people saying they rank high or very high on the ethical spectrum. Clergy came in seventh of the 22 professions ranked.
The overall trend for clergy has sloped downward since 2001, with Gallup pollsters attributing the slide to scandals involving the sexual abuse of minors.
But the Rev. J.C. Austin of Auburn Theological Seminary suggests another reason that the clergy's reputation has suffered. Too often, he said, divisive clergy overshadow those working toward the common good.
"We saw that this year, in particular, around the marriage equality debates when voices of faith were represented as the opposition even though countless people of faith fought for marriage equality precisely because their faith compelled them to do so," he said.