Today President Bush issued the third veto of his presidency and his second on stem cell research on a bill that would lessen restraints on federally funded embryonic stem cell research.
It's a subject that most Americans support, according to an April 2007 ABC News poll that found 68 percent of Americans support stem cell research
In a new fundraising letter, House Speaker Nancy Pelosi, D-Calif., says Bush's veto pen is taking away hope from people who might benefit from stem cell research.
However, unless the numbers on Capitol Hill change, Bush controls what has become a wrenching issue, one that is drenched in a roiling mix of politics and emotion.
"These boys and girls are not spare parts," President Bush said in July 2006.
But former first lady Nancy Reagan, the widow of conservative icon and former President Reagan, had a different view.
"I just don't see how we can turn our backs on this," she said in May 2004.
A year ago, Bush issued the first veto of his presidency and stood surrounded by the ultimate cast in the battle raging over the use of frozen embryos for stem cell research — a group of families who had "adopted" frozen embryos that were not used by other couples and then used those leftover embryos to have children.
"Each of these children was adopted while still an embryo and has been blessed with the chance to grow, to grow up in a loving family," he said at the time.
People on the other side of the debate have been equally willing to pull at a few heartstrings.
"It hurt to see the president use the one veto of his administration to strike down this legislation," actor Michael J. Fox, who suffers from Parkinson's disease, said in October 2006.
When Fox made a television commercial last year supporting stem cell research, conservative commentator Rush Limbaugh took jabs at him on his radio show.
"In this commercial, he is exaggerating the effects of the disease," Limbaugh said in October 2006.
On the day of Bush's second stem cell veto, the new media reminded everyone how potent and political the issue was. A recent pro stem cell research posting on YouTube made by a prominent Hollywood director has generated thousands of hits. The shocking video attempts to make the case that most frozen embryos are discarded.
Where Do the Candidates Stand?
Because Congress can't override a veto, any change in federal funding for stem cell research may be up to the next president. The Democrats support easing restrictions, as do Republican presidential candidates John McCain and Rudy Giuliani. But Mitt Romney, another Republican candidate, does not and he won't hesitate to play an emotional trump card.
"I have a wife that has a serious disease that could be affected by stem cell research and others," Romney said this last month, "but I will not, I will not create new embryos through cloning or through embryo farming, because that will be creating life for the purpose of destroying it."