Right you are, waxwing! Although, according to the Eggcorn database, "Tow the line may well be one of the reshapings that will soon be considered acceptable in standard English."
Well then "eggcorn" is pretty stupid. Toeing the line has a specific meaning derived from lining up for a race. Pulling the line has no sense at all.
Towing a line makes perfect sense - as in using a towing line to pull another vehicle (or ship, in a nautical context), and could easily be used to describe pulling an agenda along.
But toeing the line means staying within the existing agenda, not pulling it somewhere new.

You might as well claim that "it's" is possessive now just because everyone uses it that way.