Barack Obama's favorability rating now stands at 51 percent, Biden's at 38 percent. By contrast, 66 percent of Americans have a favorable opinion of the first lady, about even with her ratings on Inauguration Day, according to the Pew Research Center.
That's about where Laura Bush stood in the fourth year of her husband's first term, and it's considerably higher than Hillary Rodham Clinton's 42 percent at the start of her husband's fourth year as president.
Mrs. Obama is particularly popular with women and younger Americans, polling shows. And she does well with the moderate and liberal Republicans and independents whom Democrats will try to lure away in the fall elections.
There are other ways to measure her appeal: Her Twitter account shot up to more than a half-million followers in less than a month. And her Facebook page has more than 6.6 million "likes."
The first lady still has her detractors. Her anti-obesity campaign has attracted some "nanny state" grumbling from conservatives who think it intrudes on personal matters.
She said Friday that the five years since her husband announced for president actually have turned her from a natural pessimist into more of an optimist, hoping to make the most of her time in the White House.
"There's a window," she said. "Whether it's four years or eight years, it's not a lot of time."
As for how she's preparing her daughters for the coming campaign, sure to be hard-fought and bitter at times, Mrs. Obama said her focus is on reassuring the girls that "whatever happens, you guys are going to be good. So don't worry about this, just focus on your world."
Preparing them for a victory or loss, she said, "I just try to play both sides of the scenario and make both sides seem great."
So far, Mrs. Obama has headlined 32 fundraisers over the past 10 months, including six this year. Tickets to her political events range from $100 to $10,000, making them more accessible than higher-dollar fundraisers for the president. And her political schedule includes smaller cities, such as Charlottesville, Va., and Cape Elizabeth, Maine, that aren't likely to draw a presidential visit.
Still, she's hauling in millions with a fundraising stump speech that mixes a recitation of administration policy initiatives with a personal sketch of her husband as a man who stays up late after the children are in bed fretting over the concerns of ordinary Americans.
It's the same humanizing role that Mrs. Obama serves regularly in her public appearances, as she mixes public policy with stories about her own family.
What parent wouldn't think it was cool when she confessed to her dinner guests at the Olive Garden that her daughters aren't that interested in the White House kitchen garden — "because anything I do they're not interested in."
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