BOSTON (CBS) – It isn’t easy being First Lady of the United States. You are under constant scrutiny, and if you make a mistake you are fair game for the critics.

Nonetheless, when it comes to public approval, most First Ladies have done very well – until now.

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A new CNN poll finds that Melania Trump’s favorability rating has dropped sharply in the past six weeks, down to 51 percent. Her unfavorable rating is up slightly, to 29 percent.

To put this in context, President George W. Bush’s wife Laura peaked at 85 percent approval in 2005, the highest ratings in the history of the Gallup poll. Michelle Obama topped out at 79 percent approval.

And as low-rated as Hillary Clinton is these days, it’s easy to forget she had an 80 percent approval rating as First Lady in the late 1990s.

First Lady Melania Trump. (Photo by Chris Kleponis – Pool/Getty Images)

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Why is Melania Trump doing so poorly by comparison? If you look inside the poll, she lags among women, with only 46 percent holding a favorable view of her, and among people earning less than $50,000 a year, at 43 percent. And only 38 percent of voters under age 34 approve of her.

But mostly, Mrs. Trump’s popularity problems flow from her husband, who in that same CNN poll draws positive reviews from just 40 percent overall, 31 percent among women, and only ten percent of Democrats.

Is that fair?

First Ladies tend to have an identity somewhat separate from their husbands, but Mrs. Trump makes very few public appearances and her anti-cyber-bullying campaign is low-profile, to say the least.

Maybe, over time, Americans will warm up to Melania Trump. It would be unprecedented – and telling – if they did not.

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