Fusion voting
Candidates can run on several party lines, such as Working Families or Conservative, and their votes on every line are added together. The forecast counts all of a candidate's lines.
New York › U.S. House of Representatives · November 3, 2026 · Updated Oct 16, 2026
New York's 21st District
FusionConstantino is favored to win: Constantino wins in about 3 of every 4 simulations.
Gendebien (D)
29%
chance of winning
Constantino (R)
71%
- Average margin
- R+3.3
- 80% of outcomes
- R+11 to D+5
- Partisan lean
- R+20
- Polls
- 7in our database
Constantino is clearly favored to win: Constantino wins in 5 of every 6 simulations.
Gendebien (D)
16%
chance of winning
Constantino (R)
84%
- Average margin
- R+7.6
- 80% of outcomes
- R+18 to D+3
- Partisan lean
- R+20
- Polls
- 7in our database
How this race is decided
Range of outcomes
Final margin across our simulations; the white dashes mark the middle 80%.
The candidates
Democratic
Blake Gendebien
Dairy farmer and nominee for this district in the cancelled 2025 special election
- Experience
- No elected office
- Raised
- $5.5M
- From individuals
- $5.3M
- Spent
- $3.1M
- Cash on hand
- $2.6M
Money: FEC, through Jun 30, 2026.
Republican
Anthony Constantino
Businessman and candidate for this district in the canceled 2025 special election
- Experience
- No elected office
- Raised
- $9.5M
- From individuals
- $0
- Spent
- $8.7M
- Cash on hand
- $3M
Money: FEC, through Jun 30, 2026.
What goes into the forecast
Every ingredient's estimate of the final margin.
- National environment
- D+9.5Election Day forecast; federal races run in it
- Swing reaching this office
- 78%Of a shift in the environment, from past House races since 2016
- Mid-Atlantic adjustment
- +0.5How House races in the region have run against lean and environment lately
Each estimate is a margin before national and statewide uncertainty is simulated. Horizon blends polls, fundamentals and a little of the similar-places estimate, weighting each by how precise it is; Pulse uses polls and similar places only.
Fundamentals inputs
| Incumbency (+1 D, −1 R) | 0 |
| Fundraising edge (log ratio of individual money) | 5.11 |
| Elected-experience edge | 0 |
| First-term incumbent | 0 |
| Seat's last result vs. expectation | -2.18 |
| Incumbent's last result vs. expectation | 0 |
Polls
All 7 polls
| Pollster | Dates | Sample | Gendebien | Constantino | Margin | Adjusted |
|---|---|---|---|---|---|---|
| Siena University for Times Union, WPTZ and WAMC | Sep 30–Oct 6 | 496 LV | 46 | 42 | D+4 | D+3.3 |
| Impact Research for Gendebien’s campaignD-sponsored | Sep 29–Oct 4 | 500 LV | 45 | 48 | R+3 | R+8.7 |
| Public Policy Polling for The Bench, which supports GendebienD-sponsored | Sep 9–Sep 10 | 557 RV | 43 | 48 | R+5 | R+8.7 |
| Impact Research for Gendebien’s campaignD-sponsored | Aug 30–Sep 2 | 500 LV | 44 | 47 | R+3 | R+7.8 |
| J.L. Partners | Aug 15–Aug 17 | 500 LV | 40 | 50 | R+10 | R+7.2 |
| SurveyUSA for WNYT | Aug 4–Aug 8 | 612 LV | 43 | 39 | D+4 | D+4.1 |
| Impact Research for Gendebien’s campaignD-sponsored | May 26–May 31 | 500 LV | 44 | 45 | R+1 |
Adjusted: after correcting for the pollster's house effect, registered vs. likely voters, and movement in the national environment since the poll; shown for the polls carrying the most weight in today's average. Larger dots in the chart carry the most weight. Last poll: Oct 6, 2026.
The district
Lean R+20: how much more Democratic or Republican than the nation it votes for president.
Presidential vote
Precinct results re-aggregated to the current district lines.
Who lives here
- Population
- 766,013
- People per km²
- 17
- Adults with a B.A.+
- 26%
- White, no degree
- 66%of adults
- White 89%
- Hispanic 4%
- Black 2%
- Asian 1%
- Other / multiracial 5%
American Community Survey 2020–2024, aggregated from census tracts.
Past results
Results in the same-numbered district; earlier elections may have used different lines.
2024
348,763 votes · R+24.3✓ Elise M. Stefanik (R)62.1%
Paula Collins (D)37.8%
2024 President Vote in this district
355,269 two-party votes · R+20.8 · R+19.3 vs. the nation✓ Donald Trump (R)60.4%
Kamala Harris (D)39.6%
2022 Earlier district lines
294,328 votes · R+18.8✓ Elise M Stefanik (R)59.4%
Matt Castelli (D)40.6%
2020 Earlier district lines
320,784 votes · R+17.7✓ Elise M Stefanik (R)58.8%
Tedra L Cobb (D)41.1%
2020 President Vote in this district
350,372 two-party votes · R+15.9 · R+20.4 vs. the nation✓ Donald Trump (R)57.9%
Joe Biden (D)42.1%
2018 Earlier district lines
235,267 votes · R+13.9✓ Elise M Stefanik (R)56.1%
Tedra L Cobb (D)42.4%
Lynn Kahn (G)1.5%
2016 Earlier district lines
272,606 votes · R+36.8✓ Elise M Stefanik (R)65.3%
Mike Derrick (D)30.1%
Matthew J Funiciello (G)4.6%
2016 President Vote in this district
292,353 two-party votes · R+19.9 · R+22.1 vs. the nation✓ Donald Trump (R)59.9%
Hillary Clinton (D)40.1%