An expansion of federally funded embryonic stem cell research could pass the U.S. Senate with a veto-proof margin now that the chamber’s leader backs the idea, a leading sponsor of the effort said on Sunday.

But it may be harder getting the super-majority needed to override a possible presidential veto in the House of Representatives, Pennsylvania Republican Sen. Arlen Specter said.

Specter said the decision last week by Senate Majority Leader Bill Frist to defy President Bush and support legislation liberalizing the administration’s policy on stem cell research had given the effort a “big boost” in Congress.

“I think we’re on our way,” Specter, co-sponsor of a bill to expand the research, told CBS’s “Face the Nation.”

Bush, a Republican, has said he will veto any bill that extends embryonic stem cell research beyond the limits he imposed in 2001. The president is opposed because embryos are destroyed when the stem cells are extracted.

Frist, a Tennessee Republican and heart surgeon who may seek his party’s presidential nomination in 2008, broke with Bush on Friday by endorsing a bill already passed by the House — though not with a veto-proof margin — that would overturn the limits Bush imposed four years ago.

Specter said the change of heart on stem cells by the anti-abortion Frist gave political cover to lawmakers in both houses of Congress who were considering the issue.

“My analysis is that we have 62 votes at the present time, and we’ve got about 15 more people who are thinking it over. I believe that by the time the vote comes up we’ll have 67,” Specter said, referring to the two-thirds Senate majority needed to override a presidential veto.

“I think our problem … is going to be to get it in the House,” Specter added.

Separately, conservative Republican Sen. Rick Santorum said he was convinced Bush would still veto the legislation, despite the shifting politics on Capitol Hill.

“Without question the president will veto this,” Santorum, the Senate’s third-ranking Republican, told ABC’s “This Week.”

By Susan Cornwell

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