The bill immediately became law over Romney's objections, after both chambers exceeded the two-thirds vote needed to override a veto. The vote was 112-42 in the House and 35-2 in the Senate, four days after Romney's veto.

Under previous state law, scientists who wanted to conduct embryonic stem cell research in Massachusetts needed the approval of the local district attorney. The new law seeks to expand stem cell research by removing that requirement but giving the state Health Department some regulatory controls.

Allows the Cloning of Human Embryos

The Republican governor vetoed the bill last week because it allows the cloning of human embryos for use in stem cell experiments -- a practice Romney said amounts to creating life in order to destroy it.

Romney has said he supports research using either adult stem cells or cells extracted from leftover frozen embryos from fertility clinics.

The new Massachusetts law bans cloning that results in a baby, but that practice is already prohibited under federal law.

Supporters of embryonic stem cell experiments hope to transform Massachusetts into a center for cutting-edge research into the cure and treatment of spinal cord injuries and diseases like diabetes and Parkinson's.

The bill does not include any funding for the research, but Senate President Robert Travaglini, a Boston Democrat, said the Senate may consider devoting taxpayer money to the research in the future.

Critics said the bill will inevitably lead to human cloning.

"You can say all you want that it doesn't allow human cloning, but it's going to happen," said Senate Republican leader Brian Lees. "This bill went a little too far."

Supporters say those fears are unfounded.

"For someone to say ... this is about building babies in the laboratory -- that's just not true," said Democratic Sen. John Hart.

Connecticut Legislation

In Connecticut, the state House of Representatives overwhelmingly voted Tuesday to approve legislation that would endorse and fund embryonic and adult stem cell research in the state.

The bill would pour $100 million over 10 years into the evolving research, and set up guidelines and advisory panels and a peer review board to advance and regulate the research.

The legislation has been a top priority for both the Democrat-controlled General Assembly and Republican Gov. M. Jodi Rell. The Senate has already approved it, and Rell has committed to signing it.