South Carolina · Governor
Open this race on The Map ↗Alan Wilson is heavily favored to keep the South Carolina governorship in Republican hands. Predicted margin: R+12.6.
Show all others (2)
Michael Addison · Walid Hakim
Other is a combined forecast; individual estimates are not published.
Ballot eligibility alone supplies no quantitative estimate. Other is a collective share, not any named candidate’s forecast. Official ballot sources: Michael Addison (checked 2026-08-31); Walid Hakim (checked 2026-08-31).
high / low: vote share (%) in the middle 80 in 100 simulations
About this field
McMaster term-limited.
Forecast share averages the simulated vote. Win chance counts how often a candidate wins. A wider range of outcomes can give a candidate a higher win chance despite a lower average share.
Forecast history
Latest reading · Sep 13 · first published Sep 9 · 80% range · margin points R+22.2 to R+3.0. Methodology
Hover the line, tap it, or use the arrow keys to inspect its history.
About this series
This comparable series begins on September 9, 2026, when the model version changed to CTMM 2.2. Earlier readings remain in the archive and are not joined as voter movement; faded points before September 9, 2026 are reconstructions, not forecasts issued on those days.
Faded: CTMM 2.2 reconstructed history: computed after the fact with each date's available polls and environment, without expert ratings; not an issued forecast. Issued forecasts begin at the launch marker.
The polls
Ledger weighted average R+10.2Used by the forecast: 2 polls (60-day half-life) · measured R+9.4 · after the fitted poll-error shift R+11.92 recorded polls · 2 eligible for the aggregate · 2 with positive weight
| Fieldwork | Added | Pollster | Result | Sample |
|---|---|---|---|---|
| from 2026-08-12 | Hart Research Associates ↗ | R+7.0D 41% · R 48% | 600 LV | |
| from 2026-07-16 | Public Policy Polling ↗ | R+8.0D 37% · R 45% | 577 RV |
How the margin was built
Follow each contribution to the margin. Wider ribbons mean more percentage points. Tap an input for its calculation and source.
The signed totals combine at the forecast. Displayed values are rounded.
All calculations & sources
How this state voted, 2024 −17.870 points
The state's two-party presidential margin in 2024, from our own county sums — the same measurement the model's statewide terrain center is built from. Every pull below is measured from here, not from EVEN, which is why a landslide seat's listed pulls are small numbers and still land where the forecast does.
- 2024 presidential result for this state, two-party, from Call the Map's own county sums.
- Same source as Act I's 2024-president reference mark, so the origin lands on it.
Fitted model, above the terrain shown +7.975 points
What the fitted model adds on top of the starting terrain above — incumbency, past results, campaign finance and the other fitted terms — measured from that terrain rather than from EVEN. It is a comparison with the starting point already shown, not a separate input. The source detail lists the variables the fit uses.
- Fitted baseline -9.895 minus starting point -17.870 = 7.975 points.
- Fitted intercept: -6.136 points.
- 2010 White population share used by the frozen historical fit: observed input 66.715. -0.503 × ((66.715 − 77.922) / 12.864) = 0.438 points.
- gov_midterm_wh: observed input -1.000. -0.987 × ((-1.000 − 0.336) / 0.739) = 1.785 points.
- 2024 presidential lean relative to the national result: observed input -16.623. 4.163 × ((-16.623 − -4.415) / 20.258) = -2.509 points.
- Previous governor election margin: observed input -17.610. 1.755 × ((-17.610 − -3.131) / 19.227) = -1.322 points.
- gov_inc_running_signed: observed input 0.000. 2.531 × ((0.000 − -0.120) / 0.708) = 0.428 points.
- gov_inc_tenure_signed: observed input 0.000. 3.340 × ((0.000 − -0.143) / 0.902) = 0.529 points.
- The displayed arithmetic is rounded; the fitted terms use full precision. The intercept plus these five terms gives the non-ratings baseline.
- No source-verified current Gallup reading supports the former 40% / July 2026 claim. The current Gallup series ends in 2025; the Presidency Project identifies its 2026 observations as other pollsters. Use the unchanged fitted missing-value rule, not a replacement polling scale.
- Certified 2024 presidential baseline: state R+18.1, national R+1.5; subtracting the national margin gives relative lean −16.6. Source: FEC compilation of certified state results.
National environment +1.143 points
The contribution to this race’s margin, not the national polling margin itself. The race’s loading, reference level and polling blend determine how much of the national climate reaches its final forecast.
- The national environment in this edition is D+7.6. This row is its contribution to the race’s prior, not a claim that the country is D+1.1.
- The environment enters once, through the fitted governor elasticity: 0.4216 × (7.600 − 1.882, the environment the governor priors themselves imply) = +2.4; the producer rounds the contribution to +2.4.
- Polls receive 70.2% of the blend. They attenuate this contribution to +0.7 in the final center; the offset is included in the polling row.
- The elasticity is fitted on the pooled panel of contested governor races (2010–2024) with cycle-clustered standard errors; it is a measured response to the national environment, not a judgment floor.
This race’s polls −2.627 points
What this race’s own recent polling adds beyond its prior, after each poll is weighted for recency, sample size and pollster quality.
- 2 poll(s) / 2 pollster(s)
- The admitted polling average is R+10.2, after pollster, sample and recency adjustments.
- Polling contribution = 70.2% × (-10.234 − prior -14.131) = −2.6 points after component rounding.
- The prior includes national environment and expert ratings. The blend is R+11.4 before the separately disclosed candidate and formula adjustments.
Historical error calibration −1.019 points
A prior-election residual correction, when an admitted model publishes one.
- No separate historical residual correction is published in this governor edition.
Structural safeguards −0.182 points
Bounded corrections that keep the model consistent with structural facts.
- No Senate-style structural calibration is used in the governor model.
The components this edition publishes for this race, in points. “Other factors” closes the sum to the two-party structural lean exactly. Here the structural lean IS the published margin, so the walk sums to the projection exactly; nothing is left over.
| Named factor | Contribution |
|---|---|
| FundamentalsThe admitted fitted baseline. Its surviving variables differ by office; the source detail above identifies those used for this race. | −9.89 |
| This race's pollsAdmitted head-to-head polls of this race, recency- and quality-weighted. | −2.63 |
| National environmentThe national environment’s contribution to the prior. Polling can attenuate its influence; this value is not the national polling margin. | +1.14 |
| Historical calibrationThe House lane's calibration against certified past cycles. | −1.02 |
| Structural terrain safeguardA bounded pull toward presidential terrain in heavily partisan states. | −0.18 |
| Other factors | 0.00 |
Race context
- Forecast votes cast
- 1,744,814
- Forecast turnout
- 41.2% of the voting-eligible population
- 2024 presidential margin
- R+18.1
Statewide, 41.9% of the voting-eligible population is projected to cast a ballot; the lower figure above is the share projected to vote in this race.
Population profile Select a measure for its source and denominator
U.S. Census Bureau, 2022 American Community Survey 5-year estimates ↗
Coverage
1 quote
- Johnson defied odds in the SC gubernatorial primary. Now people want to know if he can do it again. scdailygazette.com/2026/09/03/j... by @jmholdman.bsky.social ↗
SC Daily Gazette · Official · Sep 3
curated state newsroom · recent Bluesky post · named-race match