A huge majority of Americans have supported stem cell research for quite some time now (yet another case of Dubya acting against the will of the citizenry).
Uh, "Does it work?" That question makes no sense. There's excellent reason to think stem cell therapy would work fantastically well in vastly improving the quality of life for tens of millions.
The only way to find out,and make it work, is through research. That's what Bush clamped down on,and Obama has allowed.
If we'd been doing the research all this time, we'd be a lot closer to treating people -- people with Alzheimer's, Parkinson's, the paralyzed, and who knows what/who else.