THE STATECRAFT BLUEPRINT
What Counts as a “Party-Line Vote”
The test isn’t unanimity within a party — it’s whether each party’s majority lands on opposite sides.
Illustrative schematic — not real vote data.
Voted Yea
Voted Nay
(20 dots = one illustrative party bloc — not a real chamber)
PARTY-LINE VOTE
BIPARTISAN VOTE
PARTY A
PARTY B
PARTY A
PARTY B
vs.
vs.
16 of 20 → YEA (80%)
17 of 20 → NAY (85%)
13 of 20 → YEA (65%)
11 of 20 → YEA (55%)
Majorities oppose → party-line vote
Majorities agree → bipartisan vote
THE DEFINITION
“A party-line vote is one on which a majority of Republicans
vote one way and a majority of Democrats vote another.”
“A bipartisan vote is one in which a majority of Republicans
and a majority of Democrats vote the same way.”
— Congressional Record (1956), Vol. 102, Pt. 11, p. 15069 · same threshold used by CQ Roll Call since 1953
Plain-language version: as long as each party’s majority ends up on opposite sides, individual
members crossing over doesn’t change whether the vote counts as party-line.
≥50%
share of each party’s votes needed on each side
1953
year CQ’s party-unity-vote series began
Source: Congressional Record (1956), Vol. 102, Pt. 11, p. 15069; CQ Roll Call, “Vote Watch Methodology” (updated 2023).
Illustrative schematic — not historical vote data. Full sourcing:
sources.md
·
data.csv
· The Statecraft Blueprint