WASHINGTON — A bill to ease federal funding restrictions on embryonic stem cell research seems destined to die from an all-but-certain presidential veto, but supporters of the measure are envisioning alternate routes forward while lauding the progress they've made.

"This shows how far we've really come," said Michael Werner, president of a Washington-based consulting firm called the Werner Group and a long-time advocate on the issue. In contrast, he recalled worries that the science might face an outright ban. But these days, he told Medical Device Daily's sister publication BioWorld Today, supporters have reached "a point where we're talking about whether there's a veto-proof majority."

In short, there's no futility in pushing the agenda.

So the Senate late Wednesday passed the "Stem Cell Research Enhancement Act of 2007" by a margin of 63-34 after two full days of debate, an expected outcome that demonstrated the issue's bipartisan support. Majority Leader Harry Reid (D-Nevada) introduced the bill earlier this year.

Of the total yeas, 44 Democrats voted in favor of the measure, designated S. 5, along with 17 Republicans. Three absent supporters will cast their lots to turn back a veto from a firmly entrenched President Bush, who reiterated his intentions earlier in the week, signaling a repeat of last summer's veto of an almost bill.

But those aggregate 66 supporters remain one vote shy of an override. In the House of Representatives, where companion legislation passed 253-174 early this year, the requisite two-thirds majority to overrule a veto appears further out of reach. A full 290 votes are needed in the lower chamber. So it would seem that supporters would have to wait until another congressional session, or another White House administration, to again try to move the needle further and overturn Bush's five-and-a-half-year-old executive order.

But Werner hinted at the possibility of a nearer-term alternative: affixing the legislative language to another bill, such as a must-pass appropriations measure. Given S. 5's support among congressional leaders, as well as the issue's popularity among the general public in various polls, it's not a far-fetched scenario. Still, it's yet to bubble up in the open.

"There have been no conversations about that yet," he said, "and nobody is really even talking about that yet. But that's clearly the next discussion that would happen." S. 5 is written to extend federal financing to cell lines created from embryos slated for discard by fertilization clinics. In addition, donors must give written consent and would not receive any monetary compensation. Those provisions mirror the House version, H.R. 3, which is sponsored by Reps. Diana DeGette (D-Colorado) and Mike Castle (R-Delaware).

But the Senate bill is slightly revised, adding language to support alternate methods of acquiring embryonic stem cells. That difference means the House must approve this final version before the legislation moves to the president. Castle is urging his colleagues, who return to town next week after their spring recess, to act quickly.

Though Bush will certainly veto S. 5, he has expressed support for another bill, S. 30, the "Hope Offered through Principled and Ethical Stem Cell Research (HOPE) Act." Sponsored by Sens. Norm Coleman (R-Minnesota) and Johnny Isakson (R-Georgia.), the so-called compromise legislation is written to expand federal funding to pluripotent stem cell lines derived from embryos incapable of surviving in the womb or that died during fertility treatments but still contain viable stem cells. Though some critics called it a cover for S. 5 opponents, and rooted in science fiction, it nonetheless passed 70-28 in the Senate.

But there are uncertainties around the science supporting such research, Werner said, calling the notion of a naturally dead embryo unclear, as well as determining such an embryo's viability. In addition, he pointed to language in S. 30 contradictory to Bush's existing restrictions. Of note, companion legislation has not arisen in the House.

This week's Senate activity evoked similar debates last summer, when a compromise bill was included in the debate on legislation to curb federal funding restrictions on embryonic stem cells. Written to authorize federal funds for research into obtaining pluripotent stem cells without destroying embryos through methods such as altered nuclear transfer, the bill passed in the Senate but not the House. That's the new language incorporated into S. 5 relative to H.R. 3. A third stem cell-related bill passed unanimously in both chambers to prohibit research on embryos from fetal farms where they could be created specifically for research, and was signed into law.

Whether or not S. 30 reaches the president's desk, it doesn't seem like the kind of legislation that's going to prompt significantly more research or drive investors to back further commercialization efforts in the embryonic stem cell field. At present, only a dozen or so companies operate in this space, which remains many years from generating a marketable product. The first clinical trials of an embryonic stem cell therapy are scheduled to begin next year. But S. 5, which Werner labeled "the bill that advances the science that's going to make a difference," sends a good signal to the financial community.

"You have to be pleased with the progress we've made over the long term," he said, "and I think that we will continue to see progress until we ultimately reach our objective, and we will. I don't think there's any doubt about that."