Only one attendee at the conference called“The Vetting: Obama, Radical Islam and the Soros Connection” showed any doubts.

After a viewing of Dreams From My Real Father, a documentary arguing that President Obama is actually the son of late Chicago labor activist and alleged Communist Party member Frank Marshall Davis, a bearded man in a blue shirt raised his hand above the din of a standing ovation.

“It’s really a leap,” he said. “There’s people cheering in here and all that, but the goal is to persuade people who are not with you right now. I don’t think that this presentation is persuasive.”

The audience of 80 or so gathered in a room at the National Press Club murmured, some shifting unhappily in their seats.

The film’s creator, Joel Gilbert, who also directed a documentary about secret audio tapes of George Harrison discussing Paul McCartney’s death, responded in thoughtful tones: ““Obama’s real biological and political father was a Soviet agent and Communist propagandist,” he said.

“It is generally accepted among anyone of common sense that the birth certificate produced by Obama was a bad forgery,” Gilbert continued, but clarified that “I know he wasn’t born in Kenya. I believe he was born at home with a midwife situation and the birth was then called in by the grandfather.”

The dissenter said no more. The general mood at the all-day conference, organized by conservative activist Cliff Kincaid, editor of TheSorosFiles.com, was collegial; many in the crowd, which skewed older, carefully took notes. The series of talks throughout the day laid out a line of attack that seeks to reconcile two contradictory schools of thought among what you might call post-Birthers: that the president is secret Muslim, and that he is a socialist or communist.

Polling in 2011 showed that the number of people who don’t think Obama was born in the U.S. declined by half after the release of his birth certificate. Disfavoring the media-carnival tactics favored by Birthers like Orly Taitz and Donald Trump, the new line of attack takes a pseudo-scholarly approach centered around the indictment of Davis, an acquaintance of Obama’s maternal grandfather and character in the president's memoir who’s also the subject of The Communist, a book by Paul Kengor, a professor of political science at Grove City College, a Christian institution in western Pennsylvania. With a little finagling, Obama’s suspected communist influences are shown to dovetail neatly with the possibility he’s a secret Muslim, and the whole theory fits together regardless of the fact that he has a valid birth certificate.

Both Kengor and Gilbert spoke at the conference, where Kengor detailed Davis’ history as a labor activist and journalist with ties to Obama via Obama’s grandfather, painting Davis as an integral figure in the president’s life. Kengor stopped short of actually claiming that Davis is Obama’s true biological father; instead, his book states that Obama’s personal and political philosophy derives, in the most important ways, from Davis’s teachings.

Davis, who died in 1987 and knew Obama’s grandfather during his later years in Hawaii, is a tailor-made bogeyman for the conspiracy-minded. A writer and editor for a number of left-leaning outlets in Chicago and Honolulu, Davis was also, Kengor says, a card-carrying Communist with a “literal direct link to the Kremlin” (this premise based on an alleged exclusive interview that one of Davis’ reporters scored with top Soviet official Vyacheslav Molotov) and a deep relationship to Obama. Davis, Kengor and Gilbert say, is mentioned 22 times in “Dreams From My Father” as “Frank.” (BuzzFeed hasn’t had time yet to check this assertion.)

In David Maraniss’ new biography of Obama, Davis is only mentioned a few times, described as a “black journalist, poet, civil rights activist, political leftist, jazz expert, and self-described ‘confirmed nonconformist’ who wore a gold earring in his pierced right ear and had been under surveillance by the Honolulu bureau of the FBI because of his past associations with the Communist party.” Maraniss writes that Davis was a friend of Obama’s maternal grandfather in Honolulu whom Obama met 10 or 15 times.

Kengor has been making the rounds with his book, which is being put out by Mercury Ink, an imprint run by Glenn Beck in partnership with publishing house Simon and Schuster. Kengor, a bespectacled man who wore a polo shirt and khakis to the conference, told BuzzFeed that he’ll be appearing on Lou Dobbs’ Fox Business show on Monday. He had limited time to talk because he was due at the Christian Broadcasting Network studios after his presentation, and answered our questions while signing copies of the book.

“Some people have said, including Glenn Beck, that if this becomes a best seller [the media] won’t ignore it, but I don’t know,” Kengor said. The media, he said, always ignores “books like this.”

As for whether or not President Obama was born in America, “That’s just not my area at all. I haven’t looked into that. The birth certificate, I just can’t comment on it.”

Gilbert’s documentary takes where Kengor leaves off: instead of simply presenting Davis as an indelible influence on the president, Gilbert constructs an entire argument that he is indeed Obama’s father. The argument is mostly built around similarities in the mens’ physical appearance (“I was convinced when I saw the eyes,” one woman in the audience said). The documentary is narrated in Obama’s voice, in the first person.

Gilbert believes that Obama’s Kenyan father “was simply a cover-up to hide this relationship” — an alleged affair between Ann Dunham, Obama’s mother, and Frank Marshall Davis. Some proof of this charge comes via a photo from the president’s Facebook page, where a section of Dunham’s arm appears darker than the rest of her body. This, Gilbert’s movie asserts, is proof that the picture was photoshopped to remove Davis and replace him with Dunham. Members of the audience gasped.

Thus the link between communism, in the form of Frank Marshall Davis, and Obama is established. The next step is to show that communism — an explicitly atheistic ideology — is inextricably linked to Islam. (The URL for this conference was, after all, LeninAndSharia.com.)

To that end, the conference featured Konstantin Preobrazhensky, a heavily accented man introduced as a former KGB agent turned journalist; he’s written nine books about the KGB. Preobrazhensky outlined the links between Islam and communism, saying that the two “have something in common in their concepts” — like a “commitment to terrorism” — and that Islam had privileges in an otherwise atheist Soviet state (Muslim boys could be circumcised, he said). In his introduction to the printed version of Preobrazhensky’s allegations, Cliff Kincaid wrote in bolded letters, “The core question we are raising in this report: are the Islamists in many cases communists with Islamic masks?”

One conference attendee, a Defense Department employee named Mark Silinsky, said he came to “Obama: The Vetting” because of his interest in “Islamism and political Islam’s connection to the American left,” a phenomenon he also called the “green-red alliance” and described as “underground.”

“They see the poor Muslims as the new proletariat,” Silinsky said. “The American left doesn’t use the word proletariat very much, but they do share a common skepticism of capitalism, of modernity, and of what they would call imperialism.”

While the fear of Islam is of the moment, Kengor believes the dangers of communism should not be forgotten. “This is a ghost from the Cold War,” he said. “They had strong influence and they do to this day.”

The hope, however small, remains that these theories will help defeat Obama in the fall.

“I think there’s enough that we see here,” Selinsky said, “that hopefully Mitt Romney will use it in his campaign.”