First lady Hillary Rodham Clinton brought her exploratory Senate campaign to the turf of her likely rival, New York City Mayor Rudolph W. Giuliani (R), for the first time today as she hosted the largest event of her month-old "listening tour," attended by an audience well known for its political disgust with the mayor.

In contrast to her "listening events" in western New York last week, today's engagement at Concord Baptist Church in the city's Bedford-Stuyvesant section of Brooklyn placed Clinton in the middle of her most loyal constituency: African American New Yorkers.

"When I look deep into the reservoir of your eyes, I feel you will make a difference," Adelaide Sanford, a member of the New York State board of regents, said to Clinton, expressing a feeling apparently shared by most of the 200 people in the audience who rose in standing ovation.

Polls put African American support of Clinton at nearly 90 percent. As in other communities where she has spoken, this Bed-Sty audience also was keen to hear her solutions for the education problems that dog its youth.

Clinton pressed that political button today by warning that the $792 billion tax cut plan passed by the Republican-controlled Congress would result in hundreds of thousands of New York children being denied access to after-school programs and would kill the Clinton administration's plan for funding thousands of new teacher positions to ease school crowding.

Clinton's first campaign foray into New York City comes on the heels of a concerted Republican effort to rally the party behind a Giuliani candidacy and prevent a fractious battle that would benefit Clinton's Democratic campaign. Though not officially announced, she is the presumed candidate for the seat to be vacated next year by Sen. Daniel Patrick Moynihan (D).

On Friday, Gov. George E. Pataki urged the party to unite behind Giuliani, his old party foe.

An outsider tarred by the GOP as a "carpetbagger," Clinton has generally scheduled her engagements as public "listening events," but she also has been holding meetings with the Democratic leadership in the towns where she appears, as well as going to private house parties hosted by supporters to meet people in a more informal setting. This evening she attended the fourth fund-raiser for her exploratory campaign; it was expected to bring in $100,000.

"We're not concerned with the Republican efforts to impose a candidate on their rank and file," said Matthew Hiltzig, spokesman for the New York State Democrats. "Rather, we're enthused about the grass-roots support for Mrs. Clinton. The contrast is even more evident at events like this."

Yet, most of what she does is tightly controlled and choreographed, including the sites for her events and the investigation of those who are to make up her audience.

Clinton spokesman Howard Wolfson said today that the Concord Baptist Church event, with its large and supportive audience, was not calculated for impact, but for "just the opportunity to listen to more New Yorkers."

African Americans are diehard supporters of both Clintons, as well as diehard foes of Giuliani. Polls show his support among blacks here in the single digits. In addition to a track record of snubbing African American politicians, Giuliani attracted intense criticism late last year and early this year for his combative stance against critics of police tactics in minority neighborhoods. This came in the wake of two high-profile police brutality cases. Giuliani's get-tough law enforcement stance has been credited with cleaning up sections of the city that once had virtually ceded to criminal elements, but it is viewed by many here -- especially blacks -- as having gone too far.

Neither Giuliani nor police brutality were mentioned during today's session, which focused on education issues such as overcrowded classrooms, lack of teacher training and lack of funding for after-school programs. Clinton, who has spent much of her adult life working on children's issues, has indicated that would be a focus of her campaign.

Listing a range of remedies for school violence, including tougher gun legislation, strong early childhood education and parental support, Clinton said, "I think it's just unfair and wrong for any child to worry about being in school . . . I think that should be our highest priority -- to protect our children."

Marie Jones, 46, mother of two, said she was concerned about every issue that was raised in the Clinton discussion. "About the after-school programs, that would be a top one," said Jones, who recounted the troubles her 15-year-old son has had with after-school idleness. "And about the teachers having more training, and all of the other stuff. . . . She came to listen, and that's important."

Dana Floyd, 22, an independent-living counselor for foster youth, said, "I didn't know that she took such an interest in it."

During the meeting, Clinton said she had been told that the last first lady to visit Bedford-Stuyvesant was Eleanor Roosevelt: "As you all know, I talk to her from time to time and she wanted particularly for me to say hello."

Clinton's joking reference to the 1996 revelation that she consulted a psychic in 1995 to have "imaginary conversations" with Roosevelt won applause and laughter from the crowd.