U.S. Senate

Why this race matters

This is the 18th closest Senate race in the forecast, 13.2 points, out of 35.

35 Senate races are on the 2026 ballot in this forecast (15 Democratic leads, 20 Republican leads). Seats that are not on the ballot are not assigned, so this is not a 100-seat chamber.

No earlier forecast of this race is archived, so there is no previous projection, date, or reason to show.

History block in the model: D+11.8. That is the office blend, not one past election.

Last same-office result in the candidate file: 2022 D+14.6. A special on the 2026 ballot is not automatically that contest.

The polling block for this race was omitted.

Counties

Every reporting unit in the race. Tap a county to open its precincts. The projected votes above are this table added up. They are not ballots cast.

Counties

County	Leader	Party	Margin	Vote share	Projected ↓
El Paso County	RMark Baisley, RMark Baisley	R	R+8.0	52.6%	304,079
Denver County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+58.0	77.7%	289,917
Jefferson County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+21.3	59.3%	288,661
Arapahoe County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+21.9	59.6%	259,873
Douglas County	RMark Baisley, RMark Baisley	R	R+5.2	51.2%	194,641
Adams County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+10.9	54.1%	186,319
Larimer County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+19.4	58.4%	180,048
Boulder County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+57.6	77.5%	156,626
Weld County	RMark Baisley, RMark Baisley	R	R+19.1	58.2%	143,614
Mesa County	RMark Baisley, RMark Baisley	R	R+22.5	59.9%	73,143
Pueblo County	RMark Baisley, RMark Baisley	R	R+3.3	50.3%	67,958
Broomfield County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+30.4	63.8%	37,384
La Plata County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+20.5	58.9%	28,492
Garfield County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+3.9	50.6%	24,252
Eagle County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+26.3	61.8%	22,196
Montrose County	RMark Baisley, RMark Baisley	R	R+30.8	64.0%	20,456
Fremont County	RMark Baisley, RMark Baisley	R	R+36.6	67.0%	20,336
Elbert County	RMark Baisley, RMark Baisley	R	R+49.3	73.3%	16,303
Delta County	RMark Baisley, RMark Baisley	R	R+33.7	65.5%	15,552
Summit County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+39.0	68.2%	14,008
Routt County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+29.6	63.5%	13,044
Teller County	RMark Baisley, RMark Baisley	R	R+33.6	65.5%	13,037
Montezuma County	RMark Baisley, RMark Baisley	R	R+19.2	58.2%	12,086
Chaffee County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+15.4	56.4%	11,511
Morgan County	RMark Baisley, RMark Baisley	R	R+46.7	72.0%	10,746
Park County	RMark Baisley, RMark Baisley	R	R+14.7	56.0%	9,617
Pitkin County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+46.1	71.7%	8,917
Gunnison County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+31.1	64.2%	8,735
Logan County	RMark Baisley, RMark Baisley	R	R+54.8	76.1%	8,115
Grand County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+1.0	49.2%	7,891
Archuleta County	RMark Baisley, RMark Baisley	R	R+12.2	54.8%	7,470
Otero County	RMark Baisley, RMark Baisley	R	R+23.7	60.5%	5,167
Las Animas County	RMark Baisley, RMark Baisley	R	R+11.0	54.2%	4,978
Alamosa County	RMark Baisley, RMark Baisley	R	R+8.3	52.8%	4,803
Clear Creek County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+19.0	58.2%	3,898
Moffat County	RMark Baisley, RMark Baisley	R	R+60.1	78.7%	3,862
Rio Grande County	RMark Baisley, RMark Baisley	R	R+20.7	59.0%	3,586
Prowers County	RMark Baisley, RMark Baisley	R	R+47.9	72.6%	2,978
Huerfano County	RMark Baisley, RMark Baisley	R	R+6.1	51.7%	2,835
San Miguel County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+52.2	74.8%	2,781
Yuma County	RMark Baisley, RMark Baisley	R	R+62.7	80.0%	2,700
Gilpin County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+15.2	56.3%	2,638
Conejos County	RMark Baisley, RMark Baisley	R	R+15.3	56.3%	2,622
Lake County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+18.9	58.1%	2,498
Ouray County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+23.7	60.5%	2,373
Custer County	RMark Baisley, RMark Baisley	R	R+33.4	65.3%	2,239
Saguache County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+6.2	51.7%	2,172
Kit Carson County	RMark Baisley, RMark Baisley	R	R+65.6	81.5%	2,141
Rio Blanco County	RMark Baisley, RMark Baisley	R	R+61.0	79.2%	2,136
Washington County	RMark Baisley, RMark Baisley	R	R+72.4	84.9%	1,624
Lincoln County	RMark Baisley, RMark Baisley	R	R+61.7	79.5%	1,488
Phillips County	RMark Baisley, RMark Baisley	R	R+59.9	78.6%	1,362
Costilla County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+17.1	57.2%	1,329
Bent County	RMark Baisley, RMark Baisley	R	R+36.1	66.7%	1,268
Baca County	RMark Baisley, RMark Baisley	R	R+67.7	82.5%	1,160
Crowley County	RMark Baisley, RMark Baisley	R	R+44.7	71.0%	987
Dolores County	RMark Baisley, RMark Baisley	R	R+50.3	73.8%	821
Sedgwick County	RMark Baisley, RMark Baisley	R	R+53.6	75.5%	787
Cheyenne County	RMark Baisley, RMark Baisley	R	R+75.1	86.3%	611
Kiowa County	RMark Baisley, RMark Baisley	R	R+71.8	84.6%	500
Jackson County	RMark Baisley, RMark Baisley	R	R+52.6	74.9%	483
Mineral County	RMark Baisley, RMark Baisley	R	R+10.8	54.1%	481
Hinsdale County	RMark Baisley, RMark Baisley	R	R+10.1	53.7%	387
San Juan County	DJohn Hickenlooper, DJohn Hickenlooper	D	D+35.0	66.2%	340

Model

1. Raw data

   2024 presidential baseline

   National R−D 1.5

   County presidential file. Not the 2026 result.

2. Raw data

   Generic ballot

   D 51.7 R 43.1 R−D -8.6

   National Wikipedia aggregate, 2026-10-30. State generic ballots, where a public poll exists, are mixed with the national swing for a race that does not have its own poll: ME, MI, NH, NY, OH. A state with no generic-ballot poll keeps the national swing and is not assigned a neighbor's.

3. Raw data

   Party identification

   Pew D+5 and Gallup D+10, blend R−D -7.3

   Pew NPORS 2026, identifiers plus leaners: Republican 43, Democratic 48. Gallup party identification plus leaners, first two quarters of 2026: Democratic 49, Republican 39. Pew is 55% of this blend and Gallup is 45%.

4. Model input

   National block

   R−D -8.1

   60% generic ballot and 40% party identification. The swing versus the 2024 presidential margin is what gets transmitted.

5. Model input

   Swing transmitted

   0.42 × -10.1 = -4.2

   No state generic-ballot poll. The generic ballot is R−D -8.6, a swing of -10.1 from the 2024 presidential margin. A race without its own poll uses that swing, not the 60/40 block. This state is not given another state's number.

6. Model input

   History block

   R−D -11.8

   Weights 2018 5 / 2024 35 / 2020 20 / 2022 40. If that office was on the ballot in 2022, that year takes the 40 and 2018 takes the 5. Otherwise 2018 keeps the 40. A missing year is filled with the 2020 result for the same office. Another office is not used. The year lines are El Paso County, the largest county, not the state total: 2018 from 2020 R+11.5 w5, 2024 from 2020 R+11.5 w35, 2020 R+11.5 w20, 2022 R+6.2 w40. The state number above is the vote-weighted sum. A 2024 county map is not copied forward unchanged.

7. Model input

   Electorate block

   R−D -15.5

   History reweighted by usual midterm turnout, plus half of the transmitted swing. Rural and presidential-only counties still move farther when the result is spread back to counties. That spread is ballot size, not the demographic file. Published ballots are the 2018 midterm canvass for this office, split by these modeled shares. They are not the 2024 presidential vote. The 2026 early-vote count is not inside this margin.

8. Model input

   Turnout block

   R−D -13.3

   Each county is weighted by its 2018 ballots divided by its 2024 presidential ballots. Small counties shrink halfway toward the state median. 2020 mail shares are not used.

9. Model input

   National environment

   R−D -16.0

   History plus the full transmitted swing. With no poll of this race, that swing is the state generic ballot mixed with the national block, or the national block alone.

10. Model input

    State environment

    R−D -13.7

    History plus 45 percent of the transmitted swing. This is a Senate and governor weight.

11. Model input

    State partisan lean

    R−D -11.0

    The 2024 presidential margin of this state, or of this district for a House race. It is heavier than the old state-environment block and is not shrunk toward the polling term.

12. Model input

    Trump popularity

    R−D -12.5

    New York Times approval average, October 29, 2026: 37.4% approve, 60.2% disapprove. Net approval -22.800000000000004. That is not a vote share. Four-tenths of the net is a margin, then scaled by this place's partisan lean (factor 1.37), so an unpopular president costs more in a Democratic state.

13. Model input

    Candidate favorability

    R−D 0.0

    John Hickenlooper's 2020 race is already in the history block, so it is not applied again as favorability.

14. Model input

    Demographics

    R−D -17.4

    One statewide block only. A county that is more college-educated or more nonwhite than the other counties in this race takes more of the transmitted swing, and a more rural county takes less. That changes this block, at its weight. It does not choose which counties move when the margin is spread back out. That spread uses ballot size. The shares are the 2012–2016 American Community Survey and the 2010 Census, from the 2018 county election-context file. Alaska is not in that file.

15. Model input

    Finance

    R−D -11.8

    No sourced spending edge. The block is history, or history shrunk toward the poll. It is not a finance model.

16. Model input

    Issues

    R−D -11.8

    No sourced issue score. Same treatment as finance. It is not a separate issue model.

17. Model input

    Polling

    Omitted

    No public poll. Rated from the generic congressional ballot, R−D -8.6. No state generic-ballot poll. The generic ballot is R−D -8.6, a swing of -10.1 from the 2024 presidential margin. A race without its own poll uses that swing, not the 60/40 block. This state is not given another state's number. There is no public poll, so there is no undecided line to split. Banned individual rows excluded: 0. One same-office miss, 2022: the poll was R−D -7.3 and the result was -14.6, miss -7.3. A single cycle is noisy, so 40 percent is kept. Capped at 2.5 points. It is added to the polling term only. It is not a separate weight. Applied to the polling term: -2.50. Public pollsters: 0. Outliers: 0. Recency half-life 16 days. Sample weight n/(n+350). A registered-voter poll is 0.90. An internal poll, or a poll sponsored by one party, is weighted 0. It is not in the average. An internal-only file is dropped. A poll that names both parties is not an internal. A poll more than 8 points from the median of the others is cut in half. Pollster quality nudges that weight by only a few percent. The same rule is used on a House poll. House district polls are likely-voter polls only.

18. Model input

    Generic ballot weight

    R−D -16.0

    This race has no independent poll, so the generic ballot is already the environment swing. It is not added a second time.

19. Model input

    Top line

    Not a House term

    Senate and governor are the top line. They are not moved by themselves.

20. Model input

    Candidate

    D+0.45 added whole

    John Hickenlooper gets 0.45. The state has not kept its last two incumbents. Overperformance is a separate term and is not added again here. John Hickenlooper's 2020 race is already in the history block, so it is not applied again. These points are not watered down to the candidate weight. The candidate weight is a separate slice of the baseline. On a Senate or governor race with three public polls and no outlier, the points stop at that poll instead of moving past it.

21. Model input

    Scandal

    None

    No candidate on this ballot is scandal-defined.

22. Model input

    Endorsements

    None

    No sourced endorsement on this ballot.

23. Model input

    Halfway floor

    Not applied

    Not applied. The state's 2024 presidential margin was inside 10 points, or there is no polling term.

24. Model input

    Pooling

    No poll to shrink toward

    Otherwise the shrink is 35%.

25. Model input

    Prediction market

    99% win probability

    John Hickenlooper 98.8% is a win probability, not a vote share. Republican win probability 1.2 from Kalshi 1.3% Republican; Polymarket 1.1% Republican. A price of 50 is a tie. Each point above 50 is 0.35 margin points, capped at 12, so the raw margin is -12.0. That margin is shrunk 40% toward the pre-market margin -11.4, which leaves -11.8. It enters once, at 5.0%. The polling term is not nudged. Books under $10,000 and primary markets are ignored.

26. Model input

    State bend

    None

    Not applied.

27. Model input

    State environment adjustment

    R−D -1.5

    The 2022 statewide margin was R−D -19.3 and the 2024 presidential margin was R−D -11.0. The country moved 1.4 from that presidential vote to the 2022 House vote. Fifteen percent of the difference is kept, capped at 1.5, so the state environment is -1.5 on top of the national swing.

28. Model input

    Early vote

    D+0.6

    Reported party on ballots already cast is D 31.9 R 24.6, a Democratic lead of 7.3 points of every ballot. At 6 days before the 2022 election that lead was 3.4. The difference is D+3.9. Fifteen percent is kept, capped at 1, so D+0.6. This is registration on the ballots returned so far, compared with the same point in the last midterm, not a count of how anyone voted and not another model's estimate of the electorate. The four age groups on the file, youngest to oldest, are 4.9%, 14.1%, 37.7%, and 43.2%. That is the state's own report of who has voted. It is read next to the county demographics already in the model. It is not a second early-vote point, and it is not another model's estimate of the electorate.

29. Model input

    Other ratings

    R−D -12.0 at 3.0%

    Cook, Sabato, Inside Elections, and the other columns on the same published tables (Decision Desk HQ, RealClearPolitics, Split Ticket, FiftyPlusOne, The Economist, Fox News, Silver Bulletin). 10 ratings, average R−D -12.0. A toss-up is 0, tilt 1.5, lean 3.5, likely 7, safe or solid 12. If this race is already further to that side, the rating does not pull it back. Mixed in after everything else, at 3.0 percent. It does not replace the poll. A seat nobody has rated is left alone.

30. Model input

    Weights

    stateLean 20.7% · trump 13.8% · favorability 12.7% · history 9.2% · candidate 6.9% · national 6.9% · electorate 5.7% · stateEnv 4.6% · turnout 3.4% · demographics 3.4% · finance 2.3% · issues 2.4% · market 4.9% · ratings 3.0%

    History is lighter. State partisan lean, Trump popularity, and candidate favorability are their own terms. A market, when it qualifies, scales every other weight and is not taken out of polling alone. Published ratings, when a race has them, are mixed in after that. They are not taken out of polling alone.

31. County-sum margin

    -13.2

    This is the sum of the county projections. Counties are not moved afterward to force this total.

32. Minor parties

    None

    Other is the 2024 presidential vote that was neither Democratic nor Republican, weighted by these counties. It is not the last forecast. A missing opponent is not Other. No Libertarian, Green, Constitution, or other minor line was on this ballot.

33. 80% interval

    -22.9 to -3.4

    10th to 90th percentile of 50,000 draws. Poll, national, state, turnout, and candidate error.

34. 95% interval

    -28.1 to 1.8

    2.5th to 97.5th percentile. Senate and governor state errors in the same state share a correlation of 0.30. The band shown is the marginal interval.