| 11/3/2022 | Selzer & Co. | 1.00 | — | 801 | — | LV | 🟡no scored polls🟡1284d old+3- 🟡
no scored polls Pollster has no historical polls with a known outcome in our database, so accuracy and bias cannot be measured. - 🟡
1284d old Poll was fielded 1284 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
D+11.8pt vs editors Across 5 historical polls where ≥2 editorial raters had rated the race (Cook / Sabato / IE / 538 / DDHQ etc.), this pollster's D-margin averaged 11.8pt MORE D-favorable than the rater consensus. Systematic D-lean relative to conventional wisdom. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 53.0 · Michael Franken 41.0 | pollarch |
| 10/27/2022 | Cygnal | 1.04 | R(D+1.8) | 600 | — | LV | 🟡1291d old⚪✓ verified 5d ago+2- 🟡
1291d old Poll was fielded 1291 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls. - 🔵
tracks editorial consensus Across 72 historical paired polls, this pollster's D-margins track the rater consensus (Cook / Sabato / IE / 538 / DDHQ etc.) with high correlation (r ≥ 0.85) and small mean delta (|Δ| ≤ 2pt). Their results align with conventional wisdom.
| Chuck Grassley 54.0 · Michael Franken 43.0 | pollarch |
| 10/25/2022 | Civiqs | 0.99 | L(D+2.5) | 623 | — | LV | 🟡bias D+2.5pt🟡1293d old+2- 🟡
bias D+2.5pt Across 22 historical scored polls the average error vs. actual margin is D+2.5pt. - 🟡
1293d old Poll was fielded 1293 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 52.0 · Michael Franken 44.0 | pollarch |
| 10/19/2022 | The Tarrance Group | 3.77 | —(D+1.1) | 600 | — | LV | 🟡3 scored polls🟡1299d old+4- 🟡
3 scored polls Pollster has only 3 historical polls with a known outcome to score against — too few for stable accuracy estimates. - 🟡
1299d old Poll was fielded 1299 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
high variance vs editorial consensus Stdev of (poll − rater consensus) across 5 historical paired polls exceeds 8pt — this pollster's results swing widely relative to where the editors place the same races. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls. - 🔵
weight 3.77 Aggregation weight is 3.77 (1.0 ≈ average). Weight is a derived metric combining historical accuracy, methodology, and recency.
| Chuck Grassley 53.0 · Michael Franken 42.0 | pollarch |
| 10/18/2022 | Change Research | 0.61 | L(D+3.7) | 1008 | — | LV | 🟠historical bias D+3.7pt🟡1300d old+3- 🟠
historical bias D+3.7pt Across 18 historical scored polls the average error vs. actual margin is D+3.7pt — a measurable house effect. - 🟡
1300d old Poll was fielded 1300 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
high variance vs editorial consensus Stdev of (poll − rater consensus) across 30 historical paired polls exceeds 8pt — this pollster's results swing widely relative to where the editors place the same races. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 48.0 · Michael Franken 45.0 | pollarch |
| 10/12/2022 | Selzer & Co. | 1.00 | — | 620 | — | LV | 🟡no scored polls🟡1306d old+3- 🟡
no scored polls Pollster has no historical polls with a known outcome in our database, so accuracy and bias cannot be measured. - 🟡
1306d old Poll was fielded 1306 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
D+11.8pt vs editors Across 5 historical polls where ≥2 editorial raters had rated the race (Cook / Sabato / IE / 538 / DDHQ etc.), this pollster's D-margin averaged 11.8pt MORE D-favorable than the rater consensus. Systematic D-lean relative to conventional wisdom. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 46.0 · Michael Franken 43.0 | pollarch |
| 10/4/2022 | Emerson College | 1.00 | —(D+0.7) | 959 | — | LV | 🟡1314d old⚪✓ verified 5d ago+3- 🟡
1314d old Poll was fielded 1314 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls. - 🔵
tracks editorial consensus Across 234 historical paired polls, this pollster's D-margins track the rater consensus (Cook / Sabato / IE / 538 / DDHQ etc.) with high correlation (r ≥ 0.85) and small mean delta (|Δ| ≤ 2pt). Their results align with conventional wisdom. - 🟢
accurate · bias D+0.7pt Across 117 historical scored polls this pollster's average error vs. actual margin is D+0.7pt — within ±1pt.
| Chuck Grassley 49.0 · Michael Franken 38.0 | pollarch |
| 10/4/2022 | Cygnal | 1.04 | R(D+1.8) | 600 | — | LV | 🟡1314d old⚪✓ verified 5d ago+2- 🟡
1314d old Poll was fielded 1314 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls. - 🔵
tracks editorial consensus Across 72 historical paired polls, this pollster's D-margins track the rater consensus (Cook / Sabato / IE / 538 / DDHQ etc.) with high correlation (r ≥ 0.85) and small mean delta (|Δ| ≤ 2pt). Their results align with conventional wisdom.
| Chuck Grassley 54.0 · Michael Franken 40.0 | pollarch |
| 9/8/2022 | Change Research | 0.61 | L(D+3.7) | 1143 | — | LV | 🟠historical bias D+3.7pt🟡1340d old+3- 🟠
historical bias D+3.7pt Across 18 historical scored polls the average error vs. actual margin is D+3.7pt — a measurable house effect. - 🟡
1340d old Poll was fielded 1340 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
high variance vs editorial consensus Stdev of (poll − rater consensus) across 30 historical paired polls exceeds 8pt — this pollster's results swing widely relative to where the editors place the same races. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 48.0 · Michael Franken 44.0 | pollarch |
| 7/14/2022 | Cygnal | 1.04 | R(D+1.8) | 600 | — | LV | 🟡1396d old⚪✓ verified 5d ago+2- 🟡
1396d old Poll was fielded 1396 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls. - 🔵
tracks editorial consensus Across 72 historical paired polls, this pollster's D-margins track the rater consensus (Cook / Sabato / IE / 538 / DDHQ etc.) with high correlation (r ≥ 0.85) and small mean delta (|Δ| ≤ 2pt). Their results align with conventional wisdom.
| Chuck Grassley 52.0 · Michael Franken 43.0 | pollarch |
| 7/13/2022 | Selzer & Co. | 1.00 | — | 597 | — | LV | 🟡no scored polls🟡1397d old+3- 🟡
no scored polls Pollster has no historical polls with a known outcome in our database, so accuracy and bias cannot be measured. - 🟡
1397d old Poll was fielded 1397 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
D+11.8pt vs editors Across 5 historical polls where ≥2 editorial raters had rated the race (Cook / Sabato / IE / 538 / DDHQ etc.), this pollster's D-margin averaged 11.8pt MORE D-favorable than the rater consensus. Systematic D-lean relative to conventional wisdom. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 47.0 · Michael Franken 39.0 | pollarch |
| 7/4/2022 | Change Research | 0.61 | L(D+3.7) | 1488 | — | LV | 🟠historical bias D+3.7pt🟡1406d old+3- 🟠
historical bias D+3.7pt Across 18 historical scored polls the average error vs. actual margin is D+3.7pt — a measurable house effect. - 🟡
1406d old Poll was fielded 1406 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
high variance vs editorial consensus Stdev of (poll − rater consensus) across 30 historical paired polls exceeds 8pt — this pollster's results swing widely relative to where the editors place the same races. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 49.0 · Michael Franken 44.0 | pollarch |
| 4/11/2022 | Change Research | 0.61 | L(D+3.7) | 1070 | — | LV | 🟠historical bias D+3.7pt🟡1490d old+3- 🟠
historical bias D+3.7pt Across 18 historical scored polls the average error vs. actual margin is D+3.7pt — a measurable house effect. - 🟡
1490d old Poll was fielded 1490 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
high variance vs editorial consensus Stdev of (poll − rater consensus) across 30 historical paired polls exceeds 8pt — this pollster's results swing widely relative to where the editors place the same races. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 45.0 · Michael Franken 42.0 | pollarch |
| 3/13/2022 | Moore Information Group | 0.40 | R(R+10.0) | 400 | — | LV | 🟠weight 0.40🟡4 scored polls+4- 🟠
weight 0.40 Aggregation weight is 0.40 (1.0 ≈ average). Weight combines historical accuracy, methodology, and recency. - 🟡
4 scored polls Pollster has only 4 historical polls with a known outcome to score against — too few for stable accuracy estimates. - 🟡
1519d old Poll was fielded 1519 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
R+6.5pt vs editors Across 8 historical polls where ≥2 editorial raters had rated the race (Cook / Sabato / IE / 538 / DDHQ etc.), this pollster's D-margin averaged 6.5pt MORE R-favorable than the rater consensus. Systematic R-lean relative to conventional wisdom. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 45.0 · Abby Finkenauer 36.0 | pollarch |
| 2/22/2022 | Cygnal | 1.04 | R(D+1.8) | 610 | — | LV | 🟡1538d old⚪✓ verified 5d ago+2- 🟡
1538d old Poll was fielded 1538 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls. - 🔵
tracks editorial consensus Across 72 historical paired polls, this pollster's D-margins track the rater consensus (Cook / Sabato / IE / 538 / DDHQ etc.) with high correlation (r ≥ 0.85) and small mean delta (|Δ| ≤ 2pt). Their results align with conventional wisdom.
| Chuck Grassley 53.0 · Abby Finkenauer 39.0 | pollarch |
| 12/13/2021 | Data for Progress | 1.00 | —(D+1.0) | 770 | — | LV | 🟡1609d old🟡high variance vs editorial consensus+3- 🟡
1609d old Poll was fielded 1609 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
high variance vs editorial consensus Stdev of (poll − rater consensus) across 127 historical paired polls exceeds 8pt — this pollster's results swing widely relative to where the editors place the same races. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls. - 🟢
accurate · bias D+1.0pt Across 50 historical scored polls this pollster's average error vs. actual margin is D+1.0pt — within ±1pt.
| Chuck Grassley 53.0 · Abby Finkenauer 39.0 | pollarch |
| 10/19/2021 | Cygnal | 1.04 | R(D+1.8) | 600 | — | LV | 🟡1664d old⚪✓ verified 5d ago+2- 🟡
1664d old Poll was fielded 1664 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls. - 🔵
tracks editorial consensus Across 72 historical paired polls, this pollster's D-margins track the rater consensus (Cook / Sabato / IE / 538 / DDHQ etc.) with high correlation (r ≥ 0.85) and small mean delta (|Δ| ≤ 2pt). Their results align with conventional wisdom.
| Chuck Grassley 55.0 · Abby Finkenauer 39.0 | pollarch |
| 9/15/2021 | Selzer & Co. | 1.00 | — | 620 | — | LV | 🟡no scored polls🟡1698d old+3- 🟡
no scored polls Pollster has no historical polls with a known outcome in our database, so accuracy and bias cannot be measured. - 🟡
1698d old Poll was fielded 1698 days ago. Older polls reflect an earlier state of the race and are weighted down in the rolling average. - 🟡
D+11.8pt vs editors Across 5 historical polls where ≥2 editorial raters had rated the race (Cook / Sabato / IE / 538 / DDHQ etc.), this pollster's D-margin averaged 11.8pt MORE D-favorable than the rater consensus. Systematic D-lean relative to conventional wisdom. - ⚪
✓ verified 5d ago auto-checked on 5/4/2026. Deterministic checks confirmed bounds + structure (percentages in [0,100], totals plausibly close to 100%, dates ordered). Source page itself was not re-fetched. - ⚪
likely-voter screen Likely-voter screen — pollster filters respondents by reported turnout intent. Generally tighter for predicting elections than registered- or adult-population polls.
| Chuck Grassley 55.0 · Abby Finkenauer 37.0 | pollarch |