New Jersey, home to scores of top drug companies, plans to spend $380 million on stem cell research to stay in the forefront of the politically sensitive field, its acting governor said on Tuesday.

Richard Codey told the state Assembly that New Jersey will spend $150 million to build the Stem Cell Institute of New Jersey, whose founding was announced last May. Voters in November will be asked to approve a bond issue of $230 million to pay for its operation.

The state already has set aside $9.5 million in public funds for the institute to be built in New Brunswick.

The commitments make New Jersey the second biggest public backer of stem cell research after California, where voters last year approved a $3 billion bond issue to fund research.

In August 2001, U.S. President George W. Bush limited the use of federal funds for stem-cell research to batches of cells, called lines, that existed at the time. He said that taxpayers who oppose the research should not have to pay for it.

Supporters say it has the potential to find a cure for such diseases as Alzheimer’s, muscular dystrophy and cancer.

“We have the commitment to make New Jersey an international center of stem cell excellence,” said Codey, a Democrat.

The acting governor took over last November from James McGreevey, who stepped down after confessing to a homosexual affair with a former aide. Codey has not said whether he will run for governor in November.

New Jersey, with one of the largest concentrations of drug companies in the world, is home to Johnson & Johnson, Merck, Schering-Plough and Wyeth, as well as dozens of smaller pharmaceutical and biotechnology companies.

Many large drug companies based elsewhere have a research and manufacturing presence in New Jersey, such as Bristol-Myers Squibb Co. and Novartis.

Dr. Ira Black, director of the stem cell institute, said it would cost about $50 million a year to run the center, which plans to conduct research using cells from different sources, including embryos.

Marie Tasy, spokeswoman for New Jersey Right to Life, said her group opposes using human embryos for research and considers the institute a “huge waste of taxpayers’ money.”