Words ~ towing the party line

Someone on Facebook said something about "towing the party line," and I had to dash over to my blog to post something about the misuse of the word.  I have visions of someone pulling (towing) something heavy ("the party") on a long line, the way this horse is towing a barge in a canal.

"Toe the line" is an idiomatic expression, according to Wikipedia, meaning either to conform to a rule or standard — or to stand poised at the starting line in a footrace.  I can use this idiom by saying that I expect people to toe the line when it comes to correct word usage.