Mac Donnell sees this as further proof of his theory. He believes the author was trying to distance himself from the early humorists with whom he was associated out West, and who populated Vanity Fair — a group known as the Phunny Phellows, who reveled in illiterate spellings and corny jokes. By the 1870s, in the heart of the New England literary establishment and neighbor to the highly serious Harriet Beecher Stowe, Clemens had loftier, if still humorous, aspirations.
Mac Donnell moved his find to the back burner, planning to publish something about it one day, but a casual mention to another Twainian let his catlike discovery out of the bag. He published his work in the scholarly Mark Twain Journal this past spring, with characteristic detail and exposition.
"We are proud and grateful to be the venue Mac Donnell chose to announce his notable finding," the editors wrote, and Twain scholar Martin Zehr wrote in the Kansas City Star that "Mac Donnell's research fills an important gap in the story by suggesting Clemens' likely familiarity with the Vanity Fair piece two years following its publication."
Not all readers can make the leap from 1861 phunny story to 1863 pen name, however. R. Kent Rasmussen, a California scholar who has edited important Twainian reference works, says that there are simple evidentiary reasons to doubt Mac Donnell's theory.
"One, we don't know for sure that he saw the Vanity Fair article," Rasmussen says. "Two, if he did see it, there is no proof he became Mark Twain because of it." But most significantly, he asked, "Why would one of the world's most creative writers have to get his name from somebody else?"
Mac Donnell acknowledges that a direct link between the article and the pen name cannot be proven definitively, and is willing to joke about it. When he lectures on his find, he'll show a slide of the Vanity Fair article with a scrawled comment in felt-tip pen in the margin: "Note to self: Use this one! S.L.C." No such evidence actually exists. The story and the debate has made its way into the Los Angeles Review of Books and the online journal Salon.com.
"I can't prove that he saw the [Vanity Fair] article, but it seems fairly obvious that he did," Mac Donnell says. "His background as a typesetter made him thoroughly familiar with the newspaper exchange system. And why did he feel that he had to make up the Captain Sellers story?"
Kerry Driscoll, a noted Twain scholar and Chair of English at the University of St. Joseph in West Hartford, says she's in the skeptics' camp, but takes a nuanced view.
"Like any great writer, [Clemens'] mind was a smelter: random tidbits of information were constantly being tossed in, melted down to some irreducible essence, and then recombined through the great heat of his creativity," she wrote in an e-mail. "…I think it quite plausible —likely, in fact, — that Twain read the 1861 Vanity Fair sketch Kevin Mac Donnell uncovered, and that the humorous names assigned to its disreputable protagonists registered —- perhaps subliminally — in his mind, resurfacing in February 1863 when he signed his letter to the Territorial Enterprise."
Steve Courtney is a journalist and biographer. His most recent book is "'We Shall Have Them With Us Always': The Ghosts of the Mark Twain House."