What is a Congressman / Congresswoman?

        

The U.S. Congress includes both the Senate and House of Representatives. So both Senators and Representatives are Congressmen.

So why do to Representatives and the media refer to Representatives as “Congressmen”? What’s the problem with the title “Representative”? Not important-sounding enough?

My Representative, my Member of the House of Representatives, Rodney Frelinghuysen, even signs his correspondence to constituents:  

Sincerely, 
Rodney P. Frelinghuysen 
Member of Congress

I don't know whether this bothers me more or the fact that he begins his robo-responses:

Dear Friend: 

What's your opinion: Member of the House of Representatives, Member of Congress, or Your House Representative?

By Steve Reichenstein