A member of the City Council from Brooklyn, Charles Barron, said yesterday he may drop out of the mayoral race and endorse the only other black candidate in the running, the borough president of Manhattan, C. Virginia Fields.

The decision, which Mr. Barron expects to make official Sunday, does not come as a surprise, as he has raised only $49,034 for the primary and has consistently polled dead last among the five Democrats looking to unseat Mayor Bloomberg.

His anticipated exit, however, does change the landscape of the primary for all of the candidates, particularly for Ms. Fields, who could pick up some key endorsements, and for a former borough president of the Bronx, Fernando Ferrer, who, analysts said, will probably suffer most from the narrowed field.

“I just think that two blacks in the race cancel each other out, and I’d like to see a black person have a real shot at this,” Mr. Barron told The New York Sun during a phone interview. “I’m going to see if she can join in our issues.”

Mr. Barron, who instead is expected to run for re-election to the council, had the backing of a nationally prominent African-American, the Reverend Al Sharpton, in the mayoral campaign. It is unclear whom Rev. Sharpton will endorse once the council member officially aborts his mayoral campaign.

Ms. Fields, who has raised less than the other three Democrats in the race and has $1.2 million in the bank, said yesterday she has had no conversations with Rev. Sharpton about a possible endorsement. She said she would welcome Mr. Barron’s support but stressed that her candidacy would not focus on black voters.

“My thing is to just make sure that we campaign heavily in all of these communities and neighborhoods,” she said. “I think it’s probably too early to know how this is going to impact one way or the other.”

Political observers said, however, that without Mr. Barron in the race, Ms Fields could more easily solidify her base. They also said the changed political landscape will make it more difficult for Mr. Ferrer to secure the black-Latino coalition he created in the 2001 race when he finished first in the Democratic primary, only to lose a runoff with the public advocate, Mark Green.

“This is a good day for Virginia Fields’s candidacy. She’s the only African-American left standing in a demographic that nobody else has a natural claim to,” the president of the political consultancy the Advance Group, Scott Levenson, said, adding that the Barron withdrawal would therefore hurt Mr. Ferrer’s campaign.

In addition to Mr. Ferrer, the current Democratic front-runner, and Ms. Fields, the candidates planning to run in the primary are the speaker of the City Council, Gifford Miller, and a congressman who represents Brooklyn and Queens, Anthony Weiner.

Mr. Barron, who met yesterday with Ms. Fields, said he would be unveiling a group called Operation Power to raise issues in the race that he wants addressed. He said if he officially decides to endorse Ms. Fields, he’ll campaign for her as if he were running.