WASHINGTON -- Gwen Ifill, the author and "PBS News Hour" correspondent, is under fire from a conservative media outlet over her decision to serve as emcee at Thursday's annual fundraiser for Whitman-Walker Health, a nonprofit community health clinic in Washington. Health and Human Services Secretary Kathleen Sebelius will receive an award at the event.

Tim Graham, director of media analysis at the Media Research Center, which runs the website Newsbusters, wrote on Thursday that Ifill was crossing an "Obama line" by emceeing the event, where Sebelius is being honored for her work in implementing the Affordable Care Act.

Graham writes that this isn't the first time Ifill has crossed "the Obama line," pointing to her 2008 book "The Breakthrough: Politics and Race in the Age Of Obama." The book examined the role of race in modern American politics and at the time, supporters of Republican Sen. John McCain argued that the book proved that Ifill, who is black, was too biased in then-Sen. Barack Obama's favor to moderate the sole vice presidential debate between then-Sen. Joe Biden (D-Del.) and then-Alaska Gov. Sarah Palin (R). Ifill moderated the debate.

Founded in 1978, Whitman-Walker Health, formerly the Whitman Walker Clinic, specializes in "HIV/AIDS care and lesbian, gay bisexual and transgender care," according to its website.

"This is the first time we've seen an emcee at a WWH event criticized," Chip Lewis, spokesman for the clinic, told HuffPost. "We're a nonprofit community healthcare center serving more than 15,000 patients a year, and we don't turn away people who can't pay for care," he said.

In his post, Graham called the clinic an "LGBT health and advocacy group." Lewis challenged that characterization. "We're not an advocacy group and we don't have a political agenda," he said. "Our agenda is quality healthcare for our community."

Lewis also noted that Ifill, who first emceed an event for the clinic in 2004, will neither introduce Sebelius on stage nor present her with the group's Partner for Life Award. "Gwen has nothing to do with presenting the award at all," he said.

The dinner and silent auction at the Carnegie Institution for Science expects to raise about $250,000 for the clinic's services from more than 400 guests, according to Lewis.

Newsbusters is a project of the conservative Media Research Center, founded in 1987 to "document, expose and neutralize liberal media bias," according to its website. Newsbusters was recently praised by The New York Times for breaking the story of the altered NBC tape of the Trayvon Martin 911 call.

CORRECTION: An earlier version of this story misspelled the name of Health and Human Services Secretary Kathleen Sebelius.