Even: Change and Siena split the 7 measures in the Crosstab Trust Index, which grades pollsters on how close their final polls came to actual results from 1998 to 2022.
| Measure | Change | Siena |
|---|---|---|
| Trust Score | 33/100 | 67/100 ★ |
| Average error how far final polls missed the result | 5.6 pts ★ | 5.7 pts |
| Versus expected error compared with what its races predicted | 0.7 worse | 0.2 better ★ |
| Consistency random miss once its tilt is removed | ±4.5 pts ★ | ±5.1 pts |
| Historical bias closer to even is better | D+3.2 | R+3.2 |
| Winners called | 71% | 89% ★ |
| Track record final polls analyzed, 1998–2022 | 102 polls | 57 polls |
| 2026 polls | 13 | 13 |
| 2026 lean versus other polls of the same races | D+0.8 ★ | D+2.7 |
| Race | Change (latest) | Siena (latest) |
|---|---|---|
| Iowa Senate | Turek 41, Hinson 44 | Turek 47, Hinson 48 (R+2.6 vs. avg) |
Compare them in the interactive Trust Index All pollster ratings
More comparisons: Siena College vs. YouGov · Change Research vs. YouGov · Emerson College vs. Siena College · Change Research vs. Emerson College · Siena College vs. University of New Hampshire Survey Center · Change Research vs. University of New Hampshire Survey Center · New York Times/Siena College vs. Siena College · Change Research vs. New York Times/Siena College
Change has the smaller average error (5.6 pts vs. 5.7 pts). Overall, even: Change and Siena split the 7 measures in the Crosstab Trust Index (Change: C+, Trust Score 33; Siena: A-, Trust Score 67).
Change (D+0.8 versus other polls of the same races) compared with Siena (D+2.7). Lean describes how a pollster's numbers compare with others; it isn't a measure of accuracy.
Yes: 1 race in Crosstab's data, including Iowa Senate.
Grades: Crosstab Trust Index, computed from FiveThirtyEight's pollster-ratings data (CC BY 4.0), 1998–2022; 2026 measures from Crosstab's polling data.
Updated 2026-10-04 · Crosstab, nonpartisan polling analysis.