Appearance-wise, many, if not most, couples look like they're a match. Like they belong together.

No one's surprised when celebrity faces as cute as Brad Pitt's and Jennifer Aniston's vow to forever stare across the breakfast table at each other. And everyone is stunned when Julia Roberts falls, even briefly, for Lyle Lovett.

In politics, first lady Laura Bush's schoolmarm prettiness is a classic cinematic counterpoint to her husband's smirking cowboy-ishness. Teresa Heinz Kerry's lovely, young-for-65 features nicely complement her patrician-looking husband's.

Of course, Dubya's dad and mom challenged our assumptions. Barbara Bush's white-haired, grandmotherly persona contrasted too sharply with hubby George's comparative youthfulness for Americans -- and "Saturday Night Live" -- not to notice.

Now we have Elizabeth and John Edwards. The Democrats' choice for vice president is so boyishly handsome that some female voters joke that they'll vote for the ticket just so they can stare at him for the next four years.

I'd seen John Edwards dozens of times on TV and in newspaper photos during the Democratic primaries, probably forming some subconscious opinion of how his wife would look. When I finally saw the couple on TV together, I gasped.

It wasn't that Elizabeth Edwards, 55, isn't attractive -- because she is. Nothing about her was different from millions of other smart, energetic and giving women whom we all know. My visceral reaction was based entirely on the unexpected fact that Mrs. Edwards is what a male friend refers to as "a big girl." Meaning she's a bit overweight.

Okay, she's fat.

The fact that many of us recoil at the very word says plenty about our repugnance to what's merely a physical description. In some people's minds, "fat" is so horrible, so contemptible, as to be unmentionable. You'd think that well over half -- 64 percent -- of Americans weren't overweight or obese. You'd think the word "fat" said something meaningful about a person's character or worth.

You'd think that fat was the worst thing a person -- especially a woman -- could be.

Kirstie Alley, the once-svelte "Cheers" star, decided four years ago to concentrate on being "a great mother." She also stopped working out and started eating everything "yummy." Today, she weighs 203 pounds and is so comfortable with her size that she plans to star in a Showtime reality series called "Fat Actress."

"My weight in the [tabloids] is being treated like a tragedy," Alley told People magazine. "Tragedies in my mind would be like AIDS, starvation, illiteracy, child abuse."

Many have commented privately on Elizabeth Edwards's weight. Yet the media have been largely mum -- even though part of what charmed many Americans who watched the Edwardses celebrating with their three kids at the Democratic convention was that they don't fit stereotype.

In fact Elizabeth Edwards's chubbiness is less troublesome than Hollywood's size-zero superstars, who set an unattractive, and dangerous, example for young girls. I'd even suggest that Edwards's weight gives her husband, well, heft.

Great-looking people often are dismissed as shallow, dumb. In a world in which penniless men who haven't worked in years leave their wives for younger, thinner types, a wealthy hunk appears deeper and smarter for standing by his once-thin wife.

Especially if that wife gained weight after losing their beloved son, 16, in a car accident and then giving birth twice more, the last time at age 50. Especially if that wife has referred to herself as the "anti-Barbie" and admits how hard it is to resist brownies while campaigning. Especially if that wife is as bright and independent as Edwards, a former bankruptcy lawyer, seems to be.

Democratic strategist Donna Brazile recalled a mini-furor erupting when Edwards appeared at a campaign event wearing a sweat suit. "I got e-mails from people saying, 'What's wrong with her?' '' said Brazile -- who as an imposing black female politico defies stereotype herself.

"But Elizabeth Edwards looks like America looks," Brazile continued. "She has gone from her Ann Taylor look to her Lane Bryant moment. And she's comfortable and confident, and can hold her own. . . . It's refreshing."

Paul Costello, an adviser to first lady Rosalynn Carter and former first lady wannabe Kitty Dukakis, thinks Edwards represents something that's missing from politics. "Everyone believes they're being spun 24 hours a day," Costello said. "When you see someone who says, 'I am what I am, and I am this size,' it just resonates. The average American is fat to obese. People look at Elizabeth . . . kids, having gone through tragedy, struggling with her weight and being honest about it, and it's appealing.

"How many people wake up and say, 'I'm the perfect size'? Probably one percent of the nation."

Still, Americans' increasing girth doesn't necessarily translate into sympathy for the chubby, said Denise Bruner, an Arlington bariatric physician. We all know that diabetes, heart disease and other illnesses are often linked to obesity. For every person who relates to Edwards's weight struggles, Bruner said, "there's another who says, 'I can lose five pounds in two weeks. . . . Why can't she?' '' A recent study among bariatric health care workers -- men and women who treat overweight patients -- found that a majority harbored prejudices against their clients, Bruner said. "They felt these people were basically lazy -- and these are the professionals who take care of them!"

Bruner's experience with obese patients made her first reaction to Edwards's figure different from mine. "I thought, 'This is a woman who's probably a wonderful caregiver,' '' Bruner said. "Someone who's making everybody else's life happen for them, who has little opportunity to carve out special time for herself."

When such women are very successful and intelligent, she said, they wonder, "Why can't I do this for myself? They can't ask for help.

"They think, 'I can argue cases in front of a judge, produce brilliant children, have a successful marriage. What's wrong with me?' "

In Edwards's case, most of us would say, "Not much." Even Bruner suggests that a presidential campaign is no place to start a weight-loss program.

"Altering your food intake and physical activity requires being in control of your time. . . . In a campaign, you're talking about incredible stress. With all that's going on in her life, dieting would be a setup for failure -- which is the last thing you'd want."

But after the election? Bruner didn't hesitate.

"Give her my number."