2026 ballot measure forecast

South Dakota Constitutional Amendment I

Tie Medicaid expansion to federal funding level

Conditions the 2022 voter-approved Medicaid expansion on the federal funding level, letting the state pull back expansion if federal matching funds drop below a set level. The forecast has Yes at 59.5 percent against the 50 percent it needs, a 83% chance to pass.

Likely to passConstitutional amendment referred by the legislatureHealth careUpdated October 17, 2026

Chance to pass

83%

2,000 simulations

Forecast Yes

59.5%

80% range 46 to 72

Needs

50%

a simple majority

Polling average

None

No public polls found

County forecast

61 of 65 counties vote Yes

No +30Yes +30Hover a county for its forecast

Where the Yes vote lands

needs 50

2035506580

History and structure: 59.5% Yes
Polls: None
Forecast: 59.5% Yes
Yes leans: Republican
Rule to pass: Simple majority. If Amendment L passes, it is unclear whether it applies to amendments on the same ballot. HJR 5001 (2025).

The campaign

Referred by GOP legislature; no campaign data found.

Also on the South Dakota ballot

Constitutional Amendment J

Only U.S. citizens may vote

>99%

Constitutional Amendment K

Create trust for unclaimed property fund

91%

Constitutional Amendment L

Require 60% to pass constitutional amendments

54%

Polls of the measure

no polls

Pollster	Sample	Ended	Yes	No	Undecided	Yes, adjusted
No public polls of this measure. The forecast rests on how comparable measures have run and how it reached the ballot.

How this is built

Constitutional Amendment I is forecast as a health care measure whose Yes vote leans Republican. Comparable measures from 2018 to 2024 set how far its Yes share moves with South Dakota's partisanship and with each county's 2024 presidential vote, and how it reached the ballot moves it further. Polls then pull the forecast toward them by recency and size, after splitting undecided voters two to one for No. Sources: sdsos.gov , thedakotascout.com. All measures.