By MIREYA NAVARRO
 
The Web site for Black Entertainment Television put the question bluntly: "Does it bother you that Hispanics now outnumber African-Americans in the U.S.?"

The response has been torrential. One visitor to the site wrote, "Blacks are beginning to experience another wave of racial bias and favoritism not in our favor." The writer complained that employers now have a preference for bilingual applicants, and bemoaned "attempts to replace our threatening stance against discrimination with a Hispanic vote."

But another cautioned: "Sounds like the same old trick to me. 'Divide and conquer.' Are we really going to let some numbers dictate how we treat one another?"

The BET.com message board is only one forum, but it has evoked some of the emotions, worries, hopes and even awkwardness that have been felt nationwide over a singular moment in American demographics. Last summer, the Census Bureau announced that Latinos had surpassed blacks as the country's largest minority, with blacks making up 13.1 percent of the population in 2002, and Hispanics 13.4 percent.

That statistical shift, years in the making, hardly came as a surprise. Yet it has captured the attention of both Latinos and blacks, who have been grappling with its meaning in meeting rooms, on radio shows and on the Internet.

Those conversations have raised hard questions: Does the ascendance of Hispanics mean a decline in the influence of blacks? Does it doom, or encourage, alliances between the two groups? Does the old formula for those alliances — shared grievances — have much meaning given the diversity of income and status even within each group?

The rising number of Latinos has not escaped the notice of whites or other groups, whether in business or politics. President Bush's recent proposal to grant temporary visas to illegal immigrants is seen by many as just the latest effort to woo the Hispanic vote. But many blacks and Hispanic Americans say the demographic milestone has special meaning for the nation's two largest minority groups, forcing them to reassess a relationship that has sometimes brought cooperation, and sometimes conflict.

Many Latinos feel their growing numbers have finally grabbed the notice of black leaders.

"They realize we're a force to be reckoned with already," said Lou Sobh, chairman of the National Association of Hispanic Automobile Dealers. "There are some African-Americans that are going to see us as a threat, but a lot see the necessity of using each other."

Mr. Sobh's group agreed last year to merge with the black-led National Association of Minority Automobile Dealers after receiving assurances that the Latinos would be equal partners.

"The census was just something that demanded the focus of attention of anyone involved in business," said Sheila Vaden-Williams, president of the latter association. Uniting with the Latino group, she said, can help her members appeal to the growing Latino market and persuade carmakers to raise the proportion of new-car dealerships owned by minorities to 15 percent from the current 5 percent.

Not every discussion has been so fruitful. When a panel of blacks and Latinos gathered last fall at the annual meeting of the Congressional Black Caucus to address the issue — "How Will the Growth of the Hispanic Population Affect the African-American Community?" — many people came away unhappy.

One panelist, Arturo Vargas, the executive director of the National Association of Latino Elected and Appointed Officials, said afterward that he felt "a degree of anger" over the hostility he sensed in questions from the mostly black audience about his stance on matters like illegal immigration and reparations for blacks. One questioner, Alona Clifton, a Democratic Party leader from the San Francisco area, said she left "extremely disappointed" that some Latino panelists like Mr. Vargas seemed uninformed about the issues she cared about.

The ill feeling has some people worried. Troubled by the way some news reports portrayed the new statistics as if Latinos were in a horse race against blacks, the Institute for Multiracial Justice in San Francisco, an organization that encourages better relations between ethnic groups, persuaded 45 Latino artists, professors and community leaders from around the country to sign an open letter "to our African-American brothers and sisters."

"In the Latino community," it said, "we will combat the competitiveness that could feed on those headlines."

The letter, sent last summer to African-American Web sites and published by several newspapers, got the biggest reaction in places with large black populations where the Latino population has soared, said Elizabeth Martinez, the institute's director. "You have neighborhoods that used to be all black and are now half Latino," she said. "People go into a hotel in Georgia, and the chambermaids used to be black and now they're Latina. The feeling is that they're taking over."

Keith Murphy, host of a radio call-in show in Milwaukee with a mostly African-American audience, devoted one show to discussing the letter. "It's still a matter of distrust," he said. "It's a feeling among African-Americans that Latinos are coming in and getting the jobs and are getting preferential treatment."

But many African-Americans and Latinos say that no two racial or ethnic groups could benefit as much from collaboration. The two find powerful common ground in their disproportionate numbers of the country's poor and their organizations' agreement on a long list of policy issues, including support for affirmative action and changes in the criminal justice system.

"We have as much or more in common than any two ethnic or racial groups in the country, and that's because of the phenomenon of racial discrimination and how it affects our community," said Hilary Shelton, director of the Washington bureau of the N.A.A.C.P.

Latinos and African-Americans need each other to pursue that joint agenda, Mr. Shelton and others said. While Latinos may dominate in sheer numbers, many are not citizens or are too young to vote, so their political clout is largely unrealized. They also have yet to achieve the power African-Americans have won in other arenas, including what one Latino leader called "gatekeeping positions" in corporations and foundations that determine hiring and funding of programs for other minorities.

In major cities like New York and Chicago, the two groups together make up a majority of the population. "Both groups have the capacity to either help or hurt each other," said Raul Yzaguirre, president of the National Council of La Raza, a civil rights group that works with African-American organizations.

But while there has been much joint work by black and Latino national groups around specific issues, alliances do not come naturally. In many places, the two groups have battled over political representation, jobs and public funding.

Many blacks and Latinos say the ideal of an enduring "rainbow coalition" is unrealistic.

Hugh Price, a former president of the National Urban League and now a senior adviser to the New York law firm Piper Rudnick, said the increasing fragmentation by class, culture and national origin within the two populations prevented much more than "floating coalitions around key issues."

Nicolas C. Vaca, a sociologist and lawyer in California, argues in his new book, "The Presumed Alliance: The Unspoken Conflict between Latinos and Blacks and What it Means for America" (Rayo, 2004), that the groups should not be expected to join forces automatically, given their differences and the tendency of ethnic groups in this country to look out for their own interests.

Some paramount concerns for many Latino organizations, like legalizing the status of illegal immigrants, conflict with those of black groups, such as the loss of unskilled jobs to those Latino workers, Mr. Vaca noted. And in places where one group dominates, as Latinos do in Miami and blacks do in Compton, Calif., he said, neither has shown more consideration for the other in sharing appointments and programs than when they had much less power.

"Whether you're an African-American in the South, or a Latino in California, you have the right to advance your own agenda," Mr. Vaca said. "To the extent they can do it cooperatively, great. To the extent they can't, they're going to have to work out some kind of strategy to avoid conflict."

Some collaborations come more easily than others.

When the Hotel Employees and Restaurant Employees International Union called attention to immigrant rights last September by replicating the freedom rides that sought to integrate interstate bus and train terminals in the South in the early 1960's, it won the blessing of the N.A.A.C.P., the Congressional Black Caucus and the Coalition of Black Trade Unionists.

When Christy Haubegger was knocking on doors in the mid-1990's to sell investors on the idea of a magazine for Hispanic women, she found a kindred soul in Ed Lewis, the chairman and chief executive of Essence Communications, which publishes Essence, a magazine for African-American women. Mr. Lewis and Ms. Haubegger paired up to start Latina magazine, which is now owned by Solera Capital, with both Essence and Ms. Haubegger as minority shareholders.

Pulling together or staying apart sometimes depends on whether the black and Latino populations in an area have comparable status and see their fates as linked, said Gary M. Segura, a political science professor at the University of Iowa who has written about "black-brown" coalitions.

In New York, for instance, the 2001 mayoral race brought together blacks and Latinos in a political alliance to back the candidacy of Fernando Ferrer, who lost the Democratic primary. But that same year in Los Angeles, Latinos overwhelmingly supported Antonio Villaraigosa, the Latino former speaker of the State Assembly, while blacks threw their support behind James K. Hahn, the white city attorney who won the race.

Mr. Segura said one factor in black support for Mr. Hahn was the tension between the groups there. "In New York there's a Latino community, but the Latino community is not perceived as marginalizing the African-American community as it does in L.A." he said.

Some Latino groups, like Puerto Ricans and Dominicans, who themselves have large black populations, find more common ground with African-Americans than others. Mr. Segura said that Hispanics who were born in the United States and speak English were much more likely to perceive similarities with black Americans than their immigrant, Spanish-speaking counterparts.

But most Latinos and African-Americans have not lived in proximity until recently because of the concentration of blacks in the South and East and of Latinos in the Southwest.

As a result, conversations between the groups are taking place for the first time in places like Gainesville, Ga. Faye Bush, director of the New Town Florist Club, said her civil rights group started meetings last year with Latino groups to start bridging a divide that opened up as Latinos grew to a third of the city's population; blacks account for about 16 percent.

"They don't interact with each other," she said of the two groups. "Language is the biggest barrier."

At the state level, the Georgia Partnerships Network, a project of the Southern Regional Council, a civil rights organization, formed in 2002 to try to increase the joint political power of blacks and Latinos by coalescing on specific issues. One is allowing illegal immigrants to get driver's licenses, said Dwayne Patterson, director of racial unity programs for the council.

"It's only a very small effort around specific issues to build a relationship of trust and respect," he said. "You have two strong entities who are entering into a partnership. That's powerful. That's unprecedented in the South."