A "Snollygoster" is a shrewd, unprincipled person, especially a politician. It's one of those extroverted and fanciful words that originated in the fast-expanding United States of the nineteenth century.
These days it’s hardly heard. Its last burst of public notice came when President Truman used it in 1952, and defined it, either in ignorance or impishness, as “a man born out of wedlockâ€. Many people put him right, some quoting this definition from the Columbus Dispatch of October 1895, with its splendid last phrase in the spirit of the original: “A Georgia editor kindly explains that ‘a snollygoster is a fellow who wants office, regardless of party, platform or principles, and who, whenever he wins, gets there by the sheer force of monumental talknophical assumnacy’.†But an American dictionary fifty years earlier had defined it simply as a shyster.
The origin of the word is unknown, though the Oxford English Dictionary suggests it may be linked to snallygoster, which some suppose to derive from the German schnelle Geister, literally a fast-moving ghost, and which was a mythical monster of vast size—half reptile, half bird—supposedly found in Maryland, and which was invented to terrify ex-slaves out of voting.
Now, you can't say that this forum isn't educational, but I think that the orignal use of the word in this thread was't quite right. "Yobbo" would have been more apropriate.