Addressing "those who do not have the will to stand up against a presidential veto," freshman Representative Zach Space, Democrat of Ohio, described his 16-year-old son's battle against juvenile diabetes and wondered aloud what awaits him as an adult.
"This research represents the only meaningful hope for a cure in my son's lifetime," Space said.
Embryonic stem cells hold the promise of medical breakthroughs because they have the ability to become any tissue in the body. But the research typically involves the destruction of their source, frozen embryos created for in vitro fertilization, a step that stirs passions over the beginning of life.
Republican Representative Virginia Foxx of North Carolina, who is blind in one eye, said she would benefit from stem-cell science to replace a detached retina. But she said the federal government should emphasize research into adult stem cells, not those derived from embryos.
"Killing human life does not have to be accomplished to create efficacious treatment for people and diseases," she said.
The legislation would lift Bush's 2001 ban on the use of federal dollars to derive new stem cells from fertilized embryos.
Bush vetoed similar legislation last year, and actor Michael J. Fox, who is battling Parkinson's disease, helped elevate the issue into prominence with political ads during last fall's congressional elections. Democrats credit the issue, among others, for helping them drive Republicans from power in Congress.
Yesterday's vote set another milestone in the new Democratic leadership's march toward passing a string of campaign promises in the early days of the new congressional session.
In the Senate, however, Democratic efforts to pass a wide-ranging ethics rule ran aground when Republicans, aided by nine Democrats, supported a more restrictive rule governing pet projects that lawmakers tuck into major legislation.
The setback slowed down the Senate's legislative pace and illustrated the brittleness of the Democratic majority. Senate Democratic leader Harry Reid of Nevada planned to work through amendments to the ethics rules through next week.
