Joseph R. Biden Jr., the Democratic candidate for vice president, suggested in remarks today that people who care about children with disabilities should be supporters of stem-cell research.

“I hear all this talk about how the Republicans are going to work in dealing with parents who have both the joy … and the difficulty of raising a child who has a developmental disability, who were born with a birth defect,” Senator Biden said, according to CNN. “Well, guess what, folks? If you care about it, why don’t you support stem-cell research?”

Near the beginning of her acceptance speech at last week’s Republican convention, Sarah Palin pledged to be a “friend and advocate in the White House” for parents of children with disabilities. Ms. Palin, the Republican vice-presidential nominee, has a baby with Down Syndrome.

She is an opponent of stem-cell research, and the Republican platform that the party’s delegates adopted last week advocates a total ban on research using embryonic stem cells. John McCain, the party’s nominee for president, has said he supports federal financing of programs that use amniotic fluid and adult stem cells, but not research involving the use of human embryos.

Senator Biden’s remarks drew a sharp response from the McCain campaign. “Barack Obama’s running mate sunk to a new low today, launching an offensive debate over who cares more about special-needs children,” said Ben Porritt, a spokesman for the McCain-Palin campaign, according to CNN. “Playing politics with this issue is disturbing.”

David Wade, a spokesman for Senator Biden, insisted that his candidate’s comments about stem-cell research were not directed specifically at Ms. Palin, CNN reported. “This is a clash of policies, not a clash of personalities,” he said.