A significant number of black Americans -- 18 percent -- said they are willing to vote for President Bush, even though his job-approval ratings in the community are quite low, according to a national opinion survey released yesterday by the Joint Center for Political and Economic Studies, an African American think tank.

In a hypothetical match-up between the presidential candidates, black Americans favored Sen. John F. Kerry to Bush, 69 to 18 percent, the survey said. But the 18 percent for Bush is 10 percentage points higher than the president's vote total in exit polling among this population in the 2000 election.

Eddie N. Williams, the center's president, said black Americans "are holding conservative positions on some wedge issues like same-sex marriage and civil unions." About half the survey's black respondents opposed marriage and civil unions for gays, compared with 39 percent of nonblack respondents.

Bush supports a constitutional amendment that recognizes marriage as a union only between a man and a woman. Kerry said he believes marriage is a union between a man and woman but does not support amending the Constitution.

In the survey, Bush received a 22 percent approval rating, while 67 percent rated him unfavorably. Kerry's approval rating was 78 percent, a solid number, the survey said, but well short of the 86 percent Al Gore received when he ran for president in 2000.

Black Americans have routinely given Democrats about 90 percent of the vote in presidential elections.

In another finding, the survey said the 63 percent of black Americans are concerned that their vote will not count, compared with 48 percent of the general population.

The center's 2000 survey was accurate within one percentage point of how black Americans would vote for Bush. But it was short by 16 percentage points on how they would vote for Gore. Still, David A. Bositis, who wrote the poll, said he did not think Bush "will get 18 percent, but he's definitely going to increase his numbers. I think it will be between 12 and 15 percent."

Boost for Stem Cell Research

Embryonic stem cell research -- and a ballot initiative to subsidize it with billions in California tax dollars -- received a major boost with the surprise endorsement of Gov. Arnold Schwarzenegger.

The move puts Schwarzenegger at odds with President Bush and many other fellow Republicans who have expressed moral concerns over conducting research on five-day-old human embryos.

The initiative, Proposition 71, would authorize the sale of $3 billion in bonds to create the California Institute for Regenerative Medicine. The private institute would funnel about $300 million a year in grants to California scientists for the next decade. By contrast, the federal government spent $25 million on embryonic stem cell research this year.

Schwarzenegger has long been a proponent of the research that scientists say could lead to treatments for diabetes, Parkinson's disease and spinal cord injuries. But analysts interpreted his silence as an indication he did not want to put the state deeper in debt.

The architects of Proposition 71 "have done something smart," he said, "which is that there are no payments due in the next five years. So that is what really made me decide to support it."

Mixed Message?

President Bush had an awkward moment yesterday on the stump when he criticized John F. Kerry for putting "a personal-injury lawyer on the ticket" and in the next breath recommended electing a personal-injury lawyer as senator in Florida.

"I urge you to vote for Mel Martinez in the Senate," Bush said, three sentences after his jab at trial lawyers. Martinez, Bush's former housing secretary, was president of the Academy of Florida Trial Lawyers -- although he does favor limiting malpractice awards.

Staff writers Ceci Connolly and Dana Milbank contributed to this report.