Wiktionary
party lines
n. (party line English)
Usage examples of "party lines".
John Quincy crossed party lines to support the purchase, which his father, too, strongly favored.
All of the exotic polities were unanimously in favor, while the Human Polity was split along party lines with a handful of conscientious abstentions.
There is considerable bantering among the brotherhood of boat owners, similar to the old neighborhood telephone party lines.
And your elected representatives vote along party lines, irrespective of the national good.