It's just a small thing, but it's a favorite peeve of mine. Newsmen, journalists, pundits, and other charlatans don't seem to understand the definition of a Congressman. The term is used as if it were synonymous with Representative. However, Congress consists of two houses, the House of Representatives and the House of the Senate. A member of either is called a Congressman. If you wish to distinguish one from the other, a Congressman may be called a Representative or a Senator.

[I know dictionary.com and others have amended their definitions to make Congressman and Representative almost synonymous, but that's just because they reflect popular usage, if even popular usage is ambiguous and wrong.]

On a related note, the House of Representatives was designed to be the Congressional representatives of the populace at large. The House of the Senate was designed to be the Congressional representatives of the States, specifically the state legislatures. The Seventeenth Amendment effectively destroyed this division of power, moving us one giant step closer to a mobocracy and destroying the Founders' vision for America.