"He was just so cute. And when she said you will have an advocate in the White House, I was like, 'Yes!' " said Bonawitz of Northeast Philadelphia, whose daughter, Vanessa, 3, was born with Down syndrome.

Advocates for the disabled across the country are saying "Yes!" to John McCain's new running mate, Sarah Palin, and not because the Alaska governor is the first woman on a GOP ticket.

The 44-year-old gave birth in April to her fifth child, a son with Down syndrome. Strongly antiabortion, she knew of his condition before the birth and went through with the pregnancy, causing both advocates for the disabled and abortion opponents to rejoice at her decision.

Chat rooms and the governor's own Web site, which featured a "Trig welcoming committee page," were filled with happy comments from other parents of children with the genetic condition, which causes an array of physical and mental challenges.

Trig's sudden celebrity comes at a time when advocates worry that broader prenatal testing could sharply reduce the number of those born with Down syndrome, which is now one in every 733 babies, according to the National Down Syndrome Society.

Doctors and advocates estimate that 85 to 90 percent of pregnant women who are given a Down syndrome diagnosis have chosen to have an abortion.

As a high-profile politician, Palin increases the visibility of a group of people who are often overlooked, said David Tolleson, executive director of the National Down Syndrome Congress.

"It brings attention to both children and adults with Down syndrome," he said. "Very often, people don't tend to think of individuals with disabilities at all, unless they know somebody with a disability."

And seeing Trig on TV with the Palins helps break down stereotypes.

"You get to see that he is a happy, healthy, normal baby in a normal functioning family. It's no longer a great unknown; it's not scary," Tolleson said. "This baby looks happy and well."

Within hours of Trig's premature birth on April 18, word spread quickly through the tight-knit Down syndrome community.

"Within two to five hours, we knew," said Mariah Drenth, cochair of the Bucks County Down Syndrome Interest Group. "E-mails went out. We were contacted right away. We got to see pictures within a couple of days.

"This is huge for us," she said.

Palin's son is seen not only as a testament to her dedication to people with disabilities, but also as a symbol of her antiabortion credentials.

Drenth said she admired Palin because "no matter what that child had or didn't have, she was having that baby because it was put in her belly." Her cochair, Diana Santoro, who supports abortion rights, said the two causes are closely connected, possibly because those who choose to have their child, regardless of the prenatal diagnosis, tend to oppose abortion.

Many advocates are seeking to insert their own positive experiences as parents of Down syndrome children into the debate, even though the medical statistics can be daunting.

The 5,500 U.S. children born each year with the condition face a variety of cognitive and physical disabilities. Most have mild to moderate retardation, and about half suffer from congenital heart defects and might require surgery.

"It can, for some families, be very difficult," said Deborah A. Driscoll, chief of the obstetrics department at the University of Pennsylvania. Driscoll was the vice chair of an American College of Obstetricians and Gynecologists committee that last year recommended all pregnant women, not just those older than 35, be offered testing for chromosome abnormalities.

She said that she didn't anticipate higher termination rates and that, in her observations, more women had been continuing their pregnancies after a positive diagnosis for Down syndrome.

Bonawitz knows the challenges of having a special-needs child. Her daughter has had surgery five times and had to go to the doctor for five different illnesses last month.

If Palin becomes vice president, she will have a lot on her plate, Bonawitz said, but she appears to have a supportive husband and older children who will care for Trig while she helps run the country.

Until this week, Bonawitz, a Republican stay-at-home mother, was leaning toward voting for Barack Obama because he didn't seem like a Washington insider, but Palin changed all that.

She's voting for Trig's mother.