Thomas Mallon is a congenial literary professional. As an English professor in the 1980s, he began reviewing for National Review and publishing historical fiction. In 1988, he resigned a tenured job at Vasser College and shortly thereafter became the literary editor and columnist for GQ. He has produced seven novels as well as five works of nonfiction, and these days his frequent bylines in national newspapers and magazines deliver a dependable brand of well-informed and unfailingly polite commentary.

In “Up From the Academe,” the introduction to his 2001 essay collection, “In Fact,” Mr. Mallon describes the dual contempt he developed for the fixation on “raceclassgender” and the hypertechnical mode of discourse that tyrannize American university campuses. These forces, in his telling, were hostile to his own “serious” interest in literature. It is thus tempting to view Mr. Mallon as a triumphant refugee migrating from the stifling academic ghetto to prosper in the glossier realms of New York publishing.

His ascent has been accompanied by a professed modesty of purpose. In another essay, “On Not Being a Poet,” Mr. Mallon confesses that, after an abortive period of composing verse in his 20s, “I have never been able to think of myself as an artist. I didn’t even know that this was an ‘issue’ for me until a therapist insisted it was. Proud of my ability to earn a living by my pen, I have always preferred to regard myself as a ‘working writer,’ a sort of small businessman who took on the most inviting assignments that would still keep his books in the black.”

A novelist who claims to be “serious” about literature yet disavows his own status as an artist inoculates his work against certain criticisms. If a novel is not to be judged as a work of art, then how? As a form of entertainment? An exercise in genre? A business proposition? Mr. Mallon might answer that he practices a kind of speculative reconstructive journalism. He has called himself a chronicler of the “suburbs” of literature and of the past. His novels relay a sense of the author as museum curator, combing the minutiae of America’s most famous plots to erect an exhibit about one or another tastefully selected subplot. “Henry and Clara” (1994), Mr. Mallon’s bestknown book, is the story of the couple sitting next to Lincoln the night of his assassination. This tangential approach to history is designed to convey what another sometime historical novelist, Don DeLillo, has called “the inner life of the culture.”

“Fellow Travelers” (Pantheon, 354 pages, $25), Mr. Mallon’s new novel, is concerned with the overreaching of Senator Joseph McCarthy, the Republican of Wisconsin whose anticommunist crusade earned him the censure of his chamber. The fiction follows Hawkins Fuller, a Harvard-educated State Department functionary, and Timothy Laughlin, an earnest aide to Senator Charles Potter, Republican of Michigan. They are “fellow travelers” in the sense of being lovers, and therefore suspect employees of a federal apparatus probed by the Miscellaneous M Unit for “sexual subversives” whose closeted indiscretions might render them “blackmailable.”

The novel explores this intriguing premise through a series of 42 set pieces, conscientiously dated, running from the eve of McCarthy’s wedding (September 28, 1953) to the morning after his funeral (May 7, 1957). Most chapters open with a dizzying display of lost period details, gleaned no doubt from Mr. Mallon’s diligent dredging of the archives. Some backroom inventions notwithstanding, he intelligibly delineates the arc of McCarthy’s fall in pursuit of the “pink dentists” in the ranks of the U.S. Army, but beyond the central story line, the historical material Mr. Mallon proffers — much of it gossip tossed into his characters’ idle banter — is largely ephemera, and thus the experience of reading “Fellow Travelers” is akin to spending hours in a microfiche booth as four years’ worth of newspapers flash before the eye. The curiosities stuffed into every page have a cumulative effect of narrative drag on the romance of Hawk and Tim.

Their affair begins with charm as the two men meet cute outside McCarthy’s wedding reception, and the string of breakups and reunions that ensues is not without poignancy. In constructing these characters, however, Mr. Mallon is willfully schematic. “Each of us,” he has written elsewhere, “like it or not, is born to embody at least one iron law of demographics.” Hawk, by that light, personifies the privileged dandy, coasting through life with a nihilistic recklessness until the waning of his family’s fortunes moves him to marry a deep-pocketed beard. Tim, meanwhile, enacts the contradiction of being at once gay and a faithful Irish Catholic; he brings to the coupling — his first — the ardency of the believer, a capacity that also animates his growing anticommunism. So to these iron demographic laws — the unfeeling WASP and the passionate Catholic — we can add that old cliché: Opposites attract.

Mr. Mallon employs a third-person narration with an omniscience that accommodates the news of the day as easily it does any character’s thoughts at any moment (often they are thinking about the day’s headlines). But it is Tim who absorbs most of the narrative’s attention because the conflicts inherent in his character are projections of the problems that stir Mr. Mallon’s sympathies. Readers, too, will find Tim a sympathetic figure, and their taste for this novel will prove a function of how curious they are about the predicament of a homosexual Catholic struggling to live and love in a city propelled by “who has what on whom.” If Mr. Mallon’s treatment of that predicament is too conscientiously studied and deterministic, and if the clarity of his workmanlike prose style soon hardens into sterility, well, he does not claim to be an artist.

Mr. Lorentzen, an editor at Harper’s Magazine, last wrote for these pages on the novelist Sándor Márai.