That is just republican rhetoric and name calling... it means communist liberal and is meant to be insulting and is accusing you of being anti-American. Simply, that is where the term comes from and the reasons behind it... they consider 'communist' and 'liberal' the two worst insults so that is why they put them together.
Also, they believe that liberals are socialist because of our belief in social programs for the poor... they tie in that socialist belief with communism.. Get it? Btw, which is not true.
There really is no such thing and I should know because I am about as far to the left as a liberal can go without falling off.
I would say that 99% of the liberals are liberals because we are constitutionalists. Ppl like that guy hate the USA constitution so they try to paint a bad picture of rhetoric around liberals.
You see, they hate our constitution and the way our constitution won't allow Bush to invade our privacy. (recent ruling of the supreme court)
They don't like how the Supreme Court based legalizing abortion on a person's right to privacy in the 1st amendment.
They don't like how the 4th amendment separates church and state and won't force everybody to use their tax dollars to pay for prayer in public schools.
Things like that. They hate the constitution and the way the constitution forces them to behave civilized so they come up with name-calling rhetoric like commie lib in order to get you on the defense.