Forecast Methodology
Every ElectionLab forecast is produced using a combination of polling, historical election results, candidate quality, fundraising, incumbency, state partisanship, and subjective analyst judgment. Forecasts are updated whenever significant new information becomes available.
Polling
Polling forms the backbone of every forecast. Rather than relying on a single survey, ElectionLab calculates a weighted polling average that gives more influence to newer polls, larger samples, and higher-quality pollsters.
Older polls gradually lose weight over time, preventing outdated data from dominating the forecast.
Political Fundamentals
Polling alone rarely tells the whole story. ElectionLab evaluates:
- Incumbency
- State and district partisanship
- Recent voting trends
- National political environment
- Candidate quality
- Fundraising
- Political scandals
- Historical overperformance
Forecast Ratings
ElectionLab uses five race ratings.
| Rating | Probability |
|---|---|
| Safe | 99% - 1% |
| Likely | 80% - 98% |
| Lean | 61% - 79% |
| Toss-up | 40% - 60% |
Forecast Philosophy
Election forecasting is inherently uncertain. Every ElectionLab projection represents a probability—not a prediction of what must happen.
A candidate with an 80% chance of winning will still lose about one out of every five similar elections.
Our ratings should be viewed as estimates based on the best available evidence at the time they are published.
Independence
ElectionLab is an independent forecasting project.
Forecasts are not influenced by political parties, campaigns, advocacy organizations, or donors.
Every rating reflects our own judgment after reviewing polling, election history, demographics, candidate strength, and current political conditions.
Polling Average Method
ElectionLab's polling averages are designed to reflect the current state of a race rather than simply averaging every available poll.
- Newer polls receive more weight than older polls.
- Larger sample sizes receive more weight than smaller surveys.
- Likely voter polls receive slightly more weight than registered voter polls.
- Higher-quality pollsters may receive additional weighting.
- Polling averages update automatically as new polls are published.
Transparency
ElectionLab is committed to making its methodology easy to understand. Whenever our forecast changes meaningfully, the reason should be visible through updated polling, candidate information, or race analysis.
As ElectionLab continues to grow, additional statistical models, historical datasets, and forecasting tools will be incorporated while maintaining the same commitment to transparency.