Races · Senate · 2026 · South Dakota
Senate · class II · open seat
Julian Beaudion vs Mike Rounds
Where this race stands
VerifiedSafe R · model 99% R
Polling average rates this race Safe R (R+22.3, sourced from polls).
The poliagg-v34 ensemble forecasts R+27.5 with an 80% CI ranging from R+37.8 (10th pctile) to R+17.2 (90th pctile), giving R a 99% chance of winning.
This race was decisive in 10.3% of chamber-control simulations — one of the most consequential seats this cycle.
Uncertainty score: 70/100 (high). Key drivers: wide forecast CI (20.5pp); models disagree by 12.3pp. Treat any single point estimate with extra caution.
CITATIONS · safe-r · high-tipping · uncertainty-high
How confident are we?0 = certain · 100 = max uncertain
Combined
70
High uncertainty
Main driver: wide forecast CI (20.5pp).
Forecast CI width68
20.5pp 80% interval
Forecast CI width
Contribution68 / 100
Measured20.5pp 80% interval
Each driver is scaled 0–100; higher pushes the combined uncertainty score up. Lower it with more recent, tightly-clustered polls and models that agree.
Inter-model disagreement62
12.3pp across models
Inter-model disagreement
Contribution62 / 100
Measured12.3pp across models
Each driver is scaled 0–100; higher pushes the combined uncertainty score up. Lower it with more recent, tightly-clustered polls and models that agree.
Pollster dispersion0
0.0pp cross-pollster spread
Pollster dispersion
Contribution0 / 100
Measured0.0pp cross-pollster spread
Each driver is scaled 0–100; higher pushes the combined uncertainty score up. Lower it with more recent, tightly-clustered polls and models that agree.
Polling sparsity75
2 polls in 60d · target ≥ 8
Polling sparsity
Contribution75 / 100
Measured2 polls in 60d · target ≥ 8
Each driver is scaled 0–100; higher pushes the combined uncertainty score up. Lower it with more recent, tightly-clustered polls and models that agree.
Forecast · poliagg-v34
Predicted final margin
R +27.5
80% CI: R +37.8 → R +17.2 · win prob 1%
R+45R+23TIEDD+23D+45
Quality · inputs
Data quality · medium
| Polls used | 8 |
| Days to election | 118 |
| Residual σ | 8.01pt |
| Generated | 7/7/2026 |
▼ Compare with other models3 models
qgbt-v1GBT (qgbt)
R +35.7
80% CI R +36.8 → R +32.8
CV MAE 8.51
bayes-v1Bayes / Kalman
R +23.4
80% CI R +25.6 → R +21.2
CV MAE 1.72
consensusMarket-implied
R +13.9
no interval
market-implied
Polling average
Weighted, plus each pollster's measured bias subtracted before averaging.
Prediction markets
Consensus · D 8¢3 platformsupdated 11h ago
DisagreementMarkets are 17 points less bullish on D than polling. Markets 8% · polls 24%.
All polls · 8 results
strongpositiveinfocautionflag
| Date | Pollster · trust signals | n · pop | Lean | Bias · track | vs raters | D · R |
|---|---|---|---|---|---|---|
| May 29, 26 | Public Policy Polling | 726 · RV | NEUTRAL | D +0.9104 tracked | +2.4noisy | 18 · 43 |
| May 29, 26 | Public Policy Polling | 726 · RV | NEUTRAL | D +0.9104 tracked | +2.4noisy | 31 · 56 |
| May 29, 26 | Public Policy Polling | 726 · RV | NEUTRAL | D +0.9104 tracked | +2.4noisy | 44 |
| Feb 17, 26 | Public Policy Polling+1 | 685 · RV | NEUTRAL | D +0.9104 tracked | +2.4noisy | 32 · 49 |
| Feb 17, 26 | Public Policy Polling+1 | 685 · RV | NEUTRAL | D +0.9104 tracked | +2.4noisy | 47 |
| Nov 13, 25 | Public Policy Polling+2For · Internal D-aligned | 814 · RV | NEUTRAL | D +0.9104 tracked | +2.4noisy | 30 · 52 |
| Nov 13, 25 | Public Policy Polling+2For · Internal D-aligned | 814 · RV | NEUTRAL | D +0.9104 tracked | +2.4noisy | 44 |
| Jul 30, 25 | Public Policy Polling+2For · Internal D-aligned | 524 · LV | NEUTRAL | D +0.9104 tracked | +2.4noisy | 41 |
Endorsements · 3 total
Source · Wikipedia · 0 candidates with no endorsements yet1
2
Endorsements tracked
Julian Beaudion1 · 33%
Mike Rounds2 · 67%
Total3
Scraped from each candidate’s Wikipedia endorsement list.
RMike Rounds2 endorsers
Most notable · Donald Trump · president of the United States (2017–2021, 2025–present)
Elected officials1
Federal 1State 0Local 0
Elected officials · 1
- Donald Trump · president of the United States (2017–2021, 2025–present)
Organizations1
Organizations · 1
- AIPAC
DJulian Beaudion1 endorser
Most notable · Joe Biden · 46th president of the United States (2021–2025)
Elected officials1
Federal 1State 0Local 0
Elected officials · 1
- Joe Biden · 46th president of the United States (2021–2025)
Money raised · own committees
FEC Schedule E (independent expenditures) + candidate-committee totals · last filing 2026-05-28Mike RoundsS4SD00049 ↗
Receipts
$2.6M
Disburse
$1.9M
Cash on hand
$2.7M
Debts
$0
Top industries
Internet$49.4K
Internet · $49.4K
- Google · $42.2K
- Google LLC · $7.2K
Individuals $49.4K · PACs $0
Top contributors
GOOGLE$42.2K
MARQUIS MANAGEMENT, INC.$30.0K
SANFORD HEALTH$19.0K
BUSINESS OWNER$14.0K
STARKEY LABS$14.0K
Julian Beaudion
Receipts
$209.8K
Disburse
$206.8K
Cash on hand
$3.0K
Debts
$14.5K
Top industries
Education$1.0K
Education · $1.0K
- Western Michigan University · $1.0K
Individuals $1.0K · PACs $0
Top contributors
ROYZZ$5.0K
MARY CREATIVE$3.6K
BRAVELY MADE MEDIA$2.2K
SANFORD HEALTH$2.0K
HEARTSHARE SVS$1.6K
Outside spending · independent expenditures
FEC Schedule E (independent expenditures) + candidate-committee totals · 24/48-hr IE reportsIE total
$565.8K
D side
$0 · 0%
R side
$565.8K · 100%
Top spender
DEFEND AMERICAN JOBS
| Spender | Side | Amount | Share | Target |
|---|---|---|---|---|
| DEFEND AMERICAN JOBS other · boosts R
| R | $411.7K | 73% | for Mike Rounds |
| SOUTH DAKOTA CONSERVATIVE PAC super pac · boosts R
| R | $154.1K | 27% | for Mike Rounds |
Editorial ratings · 5 raters
Cook · Sabato · Inside Elections · 538 · DDHQ et al.Likely R1
Likely R · 1 rater
- The Economist · May 21
Safe R4
Safe R · 4 raters
- The Cook Political Report · Apr 12
- Inside Elections · Apr 22
- RealClearPolitics · May 18
- Sabato's Crystal Ball · Mar 3
The Cook Political Report
Safe RThe Economist
Likely RInside Elections
Safe RRealClearPolitics
Safe RSabato's Crystal Ball
Safe RDemographic crosstabs
age · education · race · genderNo demographic crosstabs published for this race yet. Most pollsters release only topline numbers; subgroup breakdowns (age, education, race, gender) appear here when a pollster publishes them.
In the news
3 shown · last 30d · Google NewsNews volume · 30d
3 articles · building history
News volume · last 30d
Articles3
Trendbuilding history
Article counts indexed by Google News; the sparkline traces weekly volume across the window.
Net favorability
0.00
Coverage lean (D−R) · first week of data
Net favorability
Score0.00
Week-over-weekfirst week of data
Tone of coverage, D minus R, scored from −1 (all R-favorable) to +1 (all D-favorable). 0 is balanced.
Coverage tilt
Neutral 100%
0% of outlets rated · by editorial lean
Coverage tilt · by outlet lean
D-leaning outlets0%
Neutral100%
R-leaning outlets0%
0% of outlets classified by editorial lean
Rating timeline
Verification trail
Polls verified7 / 8deterministic
Polls flagged1needs review
Markets ingested3 platformsupdated 11h ago
FEC filingssyncedcommittee + IE · 2026-05-28
Endorsements4 totalWikipedia scrape
News coverage3 / 30dGoogle News
Method · bounds + percentage totals + date-order checks