Alex Walter of Londonderry is just 10 years old, but he's back on the campaign trail for his second presidential primary.

Alex, who has Type 1 diabetes, joined Democratic White House hopeful Hillary Clinton at Dartmouth College on Friday as she urged the Bush administration to end its opposition to embryonic stem cell research.

Three years ago, Alex, then 7, joined Democratic presidential hopeful John Kerry on stage at a town hall forum in Hampton as Kerry attacked President Bush's stand on stem cell research.

Alex' father, Steve, said he is a registered Republican but supports Clinton because he is frustrated with the Bush administration. He said his son has endured 10 to 12 blood tests a day and about 100 insulin injections a month since being diagnosed at age 4.

"This is not a religious issue," he said. "It's really about a little boy who's 10 years old and another 100 million Americans who could benefit from this research."

Bush has threatened to veto a bill relaxing restraints on federally funded embryonic stem cell research because he says it would compel taxpayers to support "the deliberate destruction of human embryos."

Also appearing with Clinton on Friday was 23-year-old Laura Clark of Antrim, who has been paralyzed since a car crash three years ago.

Clark's mother, Kathleen, also a Republican, said her daughter's experience has been life-shattering for the family. But she also made a practical appeal for a change in policy. She said even modest advances through stem cell research - allowing quadriplegics to regain the use of their hands - would lead to a significant savings in health care costs, including the billions of dollars spent on people with chronic spinal cord injuries.

Clinton said the administration's position was part of its general contempt for science and disregard of evidence in favor of ideology.

"Every day that passes, we have families like the Walters and the Clarks waiting and wondering whether their government is really on the side of helping and saving the lives of their loved ones," she said. "Where we are now is, we're going backward. We're not just stalled. We're going backward."