House Effects
Monday, September 21, 202643 days until Election Day, November 3, 2026
House · 2026

Washington’s 3rd District

Marie Gluesenkamp Perez (D)v.John Braun (R)TOSS-UP

Incumbent: Marie Gluesenkamp Perez, currently Democratic.

Projected margin
Even
Nine in ten outcomes: D+9 to R+9
Chance of winning
50%
Marie Gluesenkamp Perez
Polls alone
R+4.1
3 polls from 3 pollsters; latest Jul 10. Weight in projection: 68%.
Fundamentals alone
D+8.8
Weight in projection: 32%.
Polls

The average over time

Each poll is first shifted by its sponsor's and its pollster's measured lean, then weighted by recency and track record. Sample size gets no weight: in 2,000-plus past races it predicted nothing about accuracy. Why.

R+10R+5EvenD+5Aug ’25OctDecFeb ’26AprJunAugOctR+4.1Election Day
adjusted weighted average shading: which side the average favors each poll, as published party-aligned pollster or sponsor
Before any poll

What the fundamentals say

A regression on past House races, fit without looking at this year. The national environment term uses the generic ballot after its historical correction (D+5.3).

What each term adds to the estimate
BaselineD+0.8
Partisan leanR+1.6
National environmentD+3.6
IncumbencyD+3.6
Incumbent's last over/under-performanceD+2.0
Fundraising gapD+0.4
Fundamentals estimateD+8.8
Input: partisan lean
R+1.8
Presidential vote relative to the nation, 2024 on this year's lines.
Input: raised from itemized individual donors, through June 30
$1.7M D · $1.2M R
FEC filings; the model uses the log of the ratio.
Handicappers, for comparison
Cook: Tossup · Sabato: Lean D · Inside Elections: Tossup
Not an input to the projection.
Table view

All 3 polls in the average

“Share” is how much of today’s average each poll supplies. It depends on recency, the pollster’s record, whether the poll screens for likely voters, and how many other polls the same firm has in the race. It does not depend on sample size.

DatesPollsterSamplePerezBraunAs publishedAdjustedShare of average
Jul 8–10Emerson CollegeDEM.-ALIGNED
for Northwest Progressive Institute
500 LV4243R+1R+4.7
moved 3.7 toward R
75%
source
Apr 25–29co/efficientREP.-ALIGNED
for NRCC
982 LV3441R+7R+2.3
moved 4.7 toward D
25%
source
Aug 1–31 ’25Voter SciencesREP.-ALIGNED
for the Washington State Republican Party
RV4148R+7R+3.3
moved 3.7 toward D
0.8%
source

LV: likely voters. RV: registered voters. A: all adults. “Adjusted” is the published margin after removing the sponsor shift and the pollster’s measured house effect; the small print says how far that moved the poll. Dem.-aligned and Rep.-aligned mark polls paid for by a party, a campaign, or an allied group, or taken by a firm whose published work is mostly for one side. They are shifted by the average lean of such polls, then counted at full weight.