Talk about your unintended consequences. A new poll shows that Oprah Winfrey’s public efforts on behalf of Barack Obama are turning off both younger and older women.

A Lifetime/Zogby poll of women shows that of those 18 to 29, almost a third said they were less likely to support the Illinois senator because of the Oprah support. Older women, over 65, also showed they were ruffled by Ms. Winfrey stepping “out of her pew,” as the daytime diva herself described it. About 17 percent of older women said the endorsement made them less likely to support Mr. Obama.

Boomer-aged women, however, were more open to Oprah’s guidance.

Among other age groups, those who disliked the endorsement were offset by an equal amount who said they were more inclined to look more favorably at Mr. Obama because of it.