Races · Senate · 2020 · Iowa

Senate · class II · open seat

Theresa Greenfield vs Joni Ernst

← Delaware Senate Illinois Senate →

Tilt RR +1.5 forecast· 45 polls · 0 markets

Model's final pre-election call · win probabilitypoliagg-v34 · final pre-election call
40% Greenfield (D)
60% Ernst (R)
Win probability
Theresa Greenfield40% (D)
Joni Ernst60% (R)
Modelpoliagg-v34 · final pre-election call
Chance of winning across many simulations of the race — not projected vote share.
R+15R+5TIEDD+5D+15
Predicted margin
Point estimateR +1.5
80% CIR+13.5 → D+10.5
The model’s central margin (D-positive) with its 80% interval — the shaded band on the scale.
Model's predicted final margin R +1.5 · 80% CI R+13.5 → D+10.5
Actual result R+6.6 · backtest (race already called)

Momentum

—

insufficient data

Tipping-point P

0.0%

Decisive for chamber control

Market · D-side

—

Cross-platform consensus

News articles · 30d

—

no recent coverage

Where this race stands

Verified

Lean R · model 60% R

No recent polls or markets for this race. PVI baseline (R+6) suggests Lean R.

The poliagg-v34 ensemble forecasts R+1.5 with an 80% CI ranging from R+13.5 (10th pctile) to D+10.5 (90th pctile), giving R a 60% chance of winning.

CITATIONS · lean-r

Forecast · poliagg-v34

Predicted final margin

R +1.5

80% CI: R +13.5 → D +10.5 · win prob 40%

R+30R+15TIEDD+15D+30

Quality · inputs

Data quality · high

Polls used	45
Days to election	passed
Actual result	R+6.6
Residual σ	6.00pt
Generated	7/1/2026

Polling average

POLL DOTSCI BAND
30354045505560ERNST 47.1GREENFIELD 46.6MAURO 42.0APR '19JAN '20NOV '20
Weighted, plus each pollster's measured bias subtracted before averaging.

All polls · 45 results

strongpositiveinfocautionflag

Date	Pollster · trust signals	n · pop	Lean	Bias · track	vs raters	D · R
Nov 1, 20	Public Policy PollingFor · Public Policy Polling	871 · unknown	NEUTRAL	D +0.9104 tracked	+2.4noisy	48 · 47
Oct 31, 20	Change Research+1For · Change Research	1,084 · LV	D-LEAN	D +3.718 tracked	+5.7noisy	48 · 47
Oct 31, 20	Civiqs/Daily KosFor · Daily Kos	853 · LV	D-LEAN	D +4.05 tracked	-0.9aligned	50 · 47
Oct 31, 20	Data for Progress+1	951 · LV	NEUTRAL	D +1.151 tracked	+0.8aligned	49 · 45
Oct 30, 20	Emerson College+1	604 · LV	NEUTRAL	D +0.7118 tracked	+0.8aligned	51 · 48
Oct 29, 20	InsiderAdvantage+1	400 · LV	R-LEAN	R +2.838 tracked	-0.5aligned	45 · 51
Oct 28, 20	Selzer & Co./Des Moines RegisterFor · The Des Moines Register	814 · LV	NEUTRAL	—	—	42 · 46
Oct 26, 20	Quinnipiac University+1For · Quinnipiac University	1,225 · LV	NEUTRAL	D +0.454 tracked	+1.1aligned	46 · 48
Oct 23, 20	RABA Research	693 · LV	NEUTRAL	—	—	51 · 45
Oct 20, 20	Emerson College+1	435 · LV	NEUTRAL	D +0.7118 tracked	+0.8aligned	46 · 51
Oct 20, 20	RMG Research	800 · LV	D-LEAN	D +6.68 tracked	+2.6d lean	46 · 43
Oct 19, 20	Siena College/NYT Upshot	753 · LV	D-LEAN	D +5.09 tracked	0.0aligned	44 · 45
Oct 18, 20	Insider Advantage+1	400 · LV	NEUTRAL	D +8.13 tracked	—	48 · 43
Oct 18, 20	Monmouth University+2For · Monmouth University Polling Institute	501 · RV	D-LEAN	D +4.520 tracked	+0.7aligned	47 · 47
Oct 10, 20	Data for Progress+1	822 · LV	NEUTRAL	D +1.151 tracked	+0.8aligned	47 · 43
Oct 8, 20	YouGov/CBS+1For · CBS News	1,022 · LV	NEUTRAL	—	—	47 · 43
Oct 7, 20	Opinion InsightFor · AAF	800 · LV	R-LEAN	—	—	45 · 47
Oct 5, 20	Civiqs/Daily KosFor · Civiqs/Daily Kos	756 · LV	D-LEAN	D +4.05 tracked	-0.9aligned	49 · 46
Oct 4, 20	Quinnipiac University+1For · Quinnipiac University	1,205 · LV	NEUTRAL	D +0.454 tracked	+1.1aligned	50 · 45
Sep 27, 20	Data for Progress+1	743 · LV	NEUTRAL	D +1.151 tracked	+0.8aligned	44 · 42
Sep 26, 20	Hart Research Associates	400 · LV	NEUTRAL	—	—	48 · 48
Sep 25, 20	RABA Research	780 · LV	NEUTRAL	—	—	51 · 39
Sep 21, 20	Monmouth University+1For · Monmouth University	402 · RV	D-LEAN	D +4.520 tracked	+0.7aligned	47 · 47
Sep 21, 20	Siena College/NYT Upshot	501 · LV	D-LEAN	D +5.09 tracked	0.0aligned	42 · 40
Sep 16, 20	Selzer/Des Moines RegisterFor · The Des Moines Register	658 · LV	NEUTRAL	—	—	45 · 42
Sep 4, 20	Fabrizio Ward/Hart Research AssociatesFor · AARP	800 · LV	NEUTRAL	—	—	45 · 50
Sep 1, 20	Opinion InsightFor · AAF	800 · LV	R-LEAN	—	—	43 · 49
Aug 13, 20	Public Policy Polling	729 · unknown	NEUTRAL	D +0.9104 tracked	+2.4noisy	48 · 45
Aug 2, 20	Monmouth University+2For · Monmouth University Polling Institute	401 · RV	D-LEAN	D +4.520 tracked	+0.7aligned	45 · 48
Aug 1, 20	Data for Progress+1	1,101 · LV	NEUTRAL	D +1.151 tracked	+0.8aligned	45 · 43
Jul 29, 20	RMG Research	500 · RV	D-LEAN	D +6.68 tracked	+2.6d lean	40 · 36
Jul 15, 20	Spry Strategies	701 · LV	NEUTRAL	—	—	45 · 43
Jun 27, 20	GQR Research+1	800 · LV	D-LEAN	—	+6.0noisy	49 · 47
Jun 9, 20	Selzer/Des Moines RegisterFor · The Des Moines Register	674 · LV	NEUTRAL	—	—	46 · 43
Jun 7, 20	Civiqs/Daily KosFor · Civiqs/Daily Kos	865 · RV	D-LEAN	D +4.05 tracked	-0.9aligned	48 · 45
Jun 3, 20	Public Policy Polling	963 · unknown	NEUTRAL	D +0.9104 tracked	+2.4noisy	45 · 43
May 8, 20	RABA Research/Eddie Mauro	632 · LV	NEUTRAL	—	—	42 · 42
Apr 30, 20	Public Policy PollingFor · Public Policy Polling	1,222 · unknown	NEUTRAL	D +0.9104 tracked	+2.4noisy	42 · 43
Mar 4, 20	Des Moines Register/Selzer & Co.For · According to a new Des Moines Register	667 · LV	NEUTRAL	—	—	41
Dec 14, 19	Public Policy Polling	944 · unknown	NEUTRAL	D +0.9104 tracked	+2.4noisy	41 · 47
Oct 15, 19	Emerson College+1	888 · RV	NEUTRAL	D +0.7118 tracked	+0.8aligned	40 · 47
Apr 29, 19	Public Policy Polling+1For · Sioux City Journal	780 · unknown	NEUTRAL	D +0.9104 tracked	+2.4noisy	48
Apr 28, 19	Lake Research Partners+1For · Iowa Starting Line	500 · LV	NEUTRAL	—	+17.7noisy	34 · 56
Apr 28, 19	Lake Research Partners+1For · Iowa Starting Line	500 · LV	NEUTRAL	—	+17.7noisy	33 · 58
Jun 30, 17	Public Policy Polling+1For · Politico	784 · unknown	NEUTRAL	D +0.9104 tracked	+2.4noisy	48

· 45 polls · 10 per page

Endorsements · 1 total

Source · Wikipedia · 2 candidates with no endorsements yet

Ernst · 100%1
Endorsements tracked
Theresa Greenfield0 · 0%
Joni Ernst1 · 100%
Total1
Scraped from each candidate’s Wikipedia endorsement list.

RJoni Ernst1 endorser

Most notable · Maggie's List

Other1

DTheresa Greenfield0 endorsers

no endorsers yet

No endorsements found yet. Endorsements come from the candidate's Wikipedia article (when one exists) and update with the daily scrape.

DEddie Mauro0 endorsers

no endorsers yet

No endorsements found yet. Endorsements come from the candidate's Wikipedia article (when one exists) and update with the daily scrape.

Money raised · own committees

FEC Schedule E (independent expenditures) + candidate-committee totals · last filing 2020-12-21

Joni ErnstS4IA00129 ↗

Receipts

$27.7M

Disburse

$28.5M

Cash on hand

$528.4K

Debts

Top industries

Securities & investment$84.5K

Air transport$22.2K

Electric utilities$14.8K

Top contributors

INFORMATION REQUESTED PER BEST EFFORTS$234.0K

BLACKSTONE$45.4K

APOLLO$39.1K

AMSCOT FINANCIAL$22.4K

RAYTHEON TECHNOLOGIES$22.2K

Theresa GreenfieldS0IA00176 ↗

Receipts

$56.4M

Disburse

$56.3M

Cash on hand

$30.2K

Debts

$188.2K

Top industries

Internet$360.5K

Computers / electronics$167.0K

Education$150.0K

Top contributors

GOOGLE$281.4K

NOT-EMPLOYED$213.3K

FACEBOOK$79.1K

MICROSOFT$72.4K

UNIVERSITY OF IOWA$62.3K

Eddie MauroS0IA00150 ↗

Receipts

$5.1M

Disburse

$5.1M

Cash on hand

$3.3K

Debts

$1.6M

Top industries

Lawyers / law firms$25.1K

Top contributors

KIRKLAND & ELLIS LLP$13.9K

KIRKLAND & ELLIS$11.2K

INTEGRITY DIRECT$8.4K

NORTHWEST PASSAGE$5.6K

RUSSO, ROSALINA, & CO$5.6K

Outside spending · independent expenditures

FEC Schedule E (independent expenditures) + candidate-committee totals · 24/48-hr IE reports

IE total

$35.4M

D side

$25.8M · 73%

R side

$9.6M · 27%

Top spender

DSCC

For / against split

For Greenfield $9.3M

Against Ernst $16.5M

Against Greenfield $6.2M

For Ernst $3.4M

Spender	Side	Amount	Share	Target
DSCC	D	$9.8M	28%	against Joni Ernst
FAMILY FRIENDLY ACTION PAC	D	$8.0M	23%	for Theresa Greenfield
IOWA VALUES ACTION	R	$5.6M	16%	against Theresa Greenfield
SMP	D	$5.2M	15%	against Joni Ernst
WOMEN VOTE!	D	$1.5M	4%	against Joni Ernst
SENATE LEADERSHIP FUND	R	$1.3M	4%	for Joni Ernst
SENATE CONSERVATIVES FUND	R	$884.1K	3%	for Joni Ernst
AMERICA'S PROGRESSIVE PROMISE PAC	D	$800.0K	2%	for Theresa Greenfield
NRSC	R	$568.6K	2%	against Theresa Greenfield
FUTURE PROGRESS	D	$164.0K	0%	for Eddie Mauro

Editorial ratings · 5 raters

Cook · Sabato · Inside Elections · 538 · DDHQ et al.

Tossup4

Lean R1

The Cook Political Report

Tossup

Oct 28

DDHQ

Tossup

Nov 2

538

Tossup

Nov 1

Inside Elections

Tossup

Oct 27

Sabato's Crystal Ball

Lean R

Nov 1

Demographic crosstabs

age · education · race · gender

No 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.

Rating timeline

Jun 22, 2026Tilt Rmodel

May 11, 2026Lean Rmodel

Verification trail

Polls verified45 / 45deterministic

Polls flagged—none

Markets ingested0 platformsnone listed

FEC filingssyncedcommittee + IE · 2020-12-21

Endorsements1 totalWikipedia scrape

News coverage< 5 articlesGoogle News

Method · bounds + percentage totals + date-order checks