On specialized websites, candidates home in

Barack Obama is glad he found BlackPlanet.com, and the social networking site for African-Americans is thrilled it found him.

Yesterday, 17 days after becoming the first presidential candidate to post his profile on BlackPlanet, Obama had attracted nearly 232,000 friends, more than he has amassed over the past year on MySpace or Facebook, the two largest online social networking communities.

On MyGrito.com, a bilingual social networking site for Latinos, Democratic hopeful Hillary Clinton outlines her "agenda to provide more opportunities for Latinos," takes weekly questions from members, and posts statements in English and Spanish on relevant issues, the most recent on National Latino AIDS Awareness Day.

Presidential candidates are increasingly turning to these specialized networking hubs - which bring people together with similar backgrounds, ethnicities, or interests - to directly target like-minded voters and potential donors with tailored messages.

BlackPlanet's success with Obama also shows how niche social networking businesses are capitalizing on the presidential campaign to raise their reputations, attract new members, and make money.

Community Connect Inc., which runs BlackPlanet and four other niche social networking sites, invited its 16 million members to be friends of Obama with the launch of his profile, a promotion usually reserved for paying customers like musicians. Community Connect gave Obama free advertisements on the BlackPlanet home page and banner ads for two weeks in exchange for the campaign's promise to update his profile at least twice a month and to provide video clips and photos, among other conditions.

"These social networking sites are easy to start, but the hard part is attracting people to them," said Fred Stutzman, an adjunct professor at the University of North Carolina at Chapel Hill who teaches a course on social networking and was a technology consultant for the Wesley Clark and John F. Kerry presidential campaigns in 2004. "Having presidential candidates coming to the sites and setting up a profile certainly adds legitimacy and can bring in new members."

Across its five sites, Community Connect saw a spike in page views and membership - the measurements social networking sites use to set advertising rates. Since Obama, who has a white mother and Kenyan father, joined two weeks ago, page views have soared more than 60 percent on its two fledgling sites, Glee.com., an online hub for the gay community, and FaithBase.com, a new site for nondenominational Christians. On Glee.com, Obama's is the most "friended" profile, with 1,248 as of yesterday.

Obama has most aggressively sought exposure on niche sites, but other presidential campaigns have taken notice and are considering boosting their presence. Last week, Community Connect officials said they started getting calls from Clinton and Democratic rival John Edwards. The New York-based company says it has promised the same treatment for all the presidential contenders.

"Our business is structured around how many members we have, how many page views we get, and we spiked with Obama," said Kay Madati, vice president of marketing. "My main interest is to generate more of these types of things, and politics works."

While Obama's campaign expressed surprise at the surge of "friends," a spokeswoman said the move fits with Obama's push to involve new and younger voters in the political process.

"His decision to launch on sites like BlackPlanet speaks to his priorities, his background, and his commitment to reaching out to people not traditionally heard from during presidential campaigns," said spokeswoman Jen Psaki.

In July, Boston-based Eons.com, a social networking site for baby boomers that claims 600,000 members, courted the campaigns to post profiles on its site. Democrats Obama, Clinton, Edwards, Joe Biden, Chris Dodd, Dennis Kucinich, and Bill Richardson and Republicans Rudy Giuliani, John McCain, and Mitt Romney have joined.

Eons, launched last year, also created Campaign Central, which lists profiles of the four most popular or active presidential contenders who have joined the site, along with political news, groups, and surveys.

Campaign Central is now one of the most visited sites and fastest-growing parts of Eons, featuring ads from national companies including Green Giant, Liberty Mutual, and Total cereal. Founder Jeff Taylor, who also launched the mammoth job search site Monster.com, said inviting candidates helped increase page views and time spent on the site.

Clinton now features a link to Eons on the bottom of her campaign website's homepage. It's one of the few online social networking sites where the New York senator, with 216 friends, has amassed more supporters than Obama, who has 151.

"We look at these sites as opportunities to reach out to people as part of robust online effort," said Peter Daou, Clinton's Internet director, adding that the campaign is looking to create several more profiles on social networking sites.

Daou and online advisers from several other campaigns said it's too early to tell how all the networking might translate into contributions or votes.

A Bentley College study of the congressional races in 2006 found that candidates with more Facebook supporters did better in the polls. Jeff Gulati, one of the authors, said while the research could not conclude whether it was cause-and-effect, the number of Facebook supporters did indicate the enthusiasm for candidates.

Still, in trying to attract the presidential hopefuls, the social networking sites have touted their membership's past voting records and voting intentions. Gather.com, a social networking site for adults, said a recent survey of its members indicated that 98.8 percent plan to vote in the 2008 presidential election.

Some political analysts say the niche networking sites are more valuable at reaching audiences than some of the broader hubs, and some offer better features than the networking giants.

For instance, Facebook, in an effort to prevent spam, prohibits people from sending bulk messages once a group reaches more than 1,000 supporters. (At a "Facebook Political Summit" in Washington, D.C., several weeks ago, the social networking giant announced plans in the future to get rid of this restriction, which campaigns have grumbled about for months.)

"In the hunt for money and volunteers, candidates leave no prospect unturned," said Christine Williams, a political science professor at Bentley College and coauthor of the 2006 study.

Jenn Abelson can be reached at abelson@globe.com.