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Primary Types and Delegate Rules by State

Use this guide to compare state primary election types, understand how presidential primaries differ from state primaries, and jump to state pages with delegate allocation details and source links.

Last reviewed: July 26, 2026. Primary election type and delegate rule information is summarized from the source links listed on this page. Confirm final rules, deadlines, and party procedures with the listed official sources.

Primary Election Type Comparison

Primary elections are one means by which a political party nominates candidates for the next general election. The main difference between a caucus and a primary is that a caucus involves face-to-face interaction between voters, where voters can try to persuade one another to vote for (or against) a certain candidate.

Primary election type comparison by state or territory
State or territoryOpenClosedPartially OpenPartially ClosedOpen to UnaffiliatedAll-ComersNonpartisanTop-TwoTop-Four
AlabamaYes
AlaskaYesYes
American SamoaYes
ArizonaYesYes
ArkansasYes
CaliforniaYesYes
ColoradoYes
ConnecticutYesYes
DelawareYes
FloridaYes
GeorgiaYes
GuamYes
HawaiiYesYes
IdahoYes
IllinoisYes
IndianaYes
IowaYes
KansasYesYes
KentuckyYes
LouisianaYesYesYes
MaineYes
MarylandYesYes
MassachusettsYes
MichiganYesYes
MinnesotaYes
MississippiYes
MissouriYesYes
MontanaYes
NebraskaYesYesYes
NevadaYesYes
New HampshireYes
New JerseyYes
New MexicoYes
New YorkYes
North CarolinaYes
North DakotaYesYes
Northern MarianasYes
OhioYes
OklahomaYesYes
OregonYesYes
PennsylvaniaYes
Puerto RicoYes
Rhode IslandYes
South CarolinaYes
South DakotaYes
TennesseeYes
TexasYes
UtahYesYes
VermontYes
Virgin IslandsYesYes
VirginiaYes
WashingtonYesYes
Washington DCYes
West VirginiaYes
WisconsinYes
WyomingYes

Open Primaries

Some states do not ask voters to choose parties on the voter registration form. These are called 'open primary' states. Voters may choose privately in which primary to vote. In other words, voters may choose which party’s ballot to vote, but this decision is private and does not register the voter with that party. This permits a voter to cast a vote across party lines for the primary election.

States With Open Primaries

States and contests classified as Open
StatePrimary election contests
AlabamaDemocratic state ; Democratic presidential ; Republican state ; Republican presidential
ArkansasDemocratic state ; Democratic presidential ; Republican state ; Republican presidential
GeorgiaDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
GuamDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
HawaiiDemocratic state ; Democratic presidential ; Republican state
MichiganDemocratic state ; Republican state
MinnesotaDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
MississippiDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
MissouriDemocratic state ; Republican state
MontanaDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
NebraskaDemocratic state ; Republican state ; Democratic congressional ; Republican congressional
North DakotaDemocratic state ; Republican state ; Democratic presidential
Puerto RicoDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
South CarolinaDemocratic state ; Republican state ; Democratic presidential ; Republican presidential
TexasDemocratic state ; Republican presidential ; Democratic presidential ; Republican state
VermontDemocratic state ; Republican state ; Democratic presidential ; Republican presidential
Virgin IslandsDemocratic state ; Republican state
VirginiaDemocratic state ; Republican state ; Democratic presidential ; Republican presidential
WisconsinDemocratic state ; Republican state ; Democratic presidential ; Republican presidential

Closed Primaries

A voter seeking to vote in a closed primary must first be a registered party member. Only registered members of a given party are allowed to vote in that party primaries. Independent or unaffiliated voters, by definition, are excluded from participating in the party nomination contests.

States With Closed Primaries

States and contests classified as Closed
StatePrimary election contests
AlaskaDemocratic presidential ; Republican presidential
American SamoaDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
ArizonaDemocratic presidential ; Republican presidential
ConnecticutDemocratic presidential ; Republican presidential
DelawareDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
FloridaDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
HawaiiRepublican presidential
KansasDemocratic presidential ; Republican presidential
KentuckyDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
LouisianaDemocratic presidential ; Republican presidential
MarylandDemocratic presidential ; Republican presidential
MichiganDemocratic presidential ; Republican presidential
MissouriDemocratic presidential ; Republican presidential
NevadaDemocratic presidential ; Republican presidential
New JerseyDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
New YorkDemocratic state ; Democratic presidential ; Republican state ; Republican presidential
North DakotaRepublican presidential
Northern MarianasDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
OklahomaDemocratic presidential ; Republican presidential
OregonDemocratic presidential ; Republican presidential
PennsylvaniaDemocratic state ; Republican state ; Democratic presidential ; Republican presidential
TennesseeDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
UtahRepublican presidential
Virgin IslandsDemocratic presidential ; Republican presidential
Washington DCDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
WyomingDemocratic state ; Republican state ; Democratic presidential ; Republican presidential

Partially Closed Primaries

State law permits political parties to choose whether to allow unaffiliated voters or voters not registered with the party to participate in their nominating contests before each election cycle. In Partially Closed Primary system, parties may let in unaffiliated voters, while still excluding members of opposing parties.

States With Partially Closed Primaries

States and contests classified as Partially Closed
StatePrimary election contests
CaliforniaDemocratic presidential ; Republican presidential
ConnecticutDemocratic state ; Republican state
IdahoDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
KansasDemocratic state ; Republican state
MarylandDemocratic state ; Republican state
OklahomaDemocratic state ; Republican state
OregonDemocratic state ; Republican state
South DakotaDemocratic state ; Republican state ; Democratic presidential ; Republican presidential
UtahDemocratic state ; Republican state ; Democratic presidential
WashingtonDemocratic presidential ; Republican presidential
West VirginiaDemocratic state ; Republican state ; Democratic presidential ; Republican presidential

Partially Open Primaries

The Partially Open Primary system allows voters to cross party lines, but they must either publicly declare their ballot choice or their ballot selection may be regarded as a form of registration with the corresponding party.

States With Partially Open Primaries

States and contests classified as Partially Open
StatePrimary election contests
IllinoisDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
IndianaDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
IowaDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
NebraskaRepublican presidential ; Democratic presidential
NevadaDemocratic state ; Republican state
OhioDemocratic state ; Democratic presidential ; Republican state ; Republican presidential

Open to Unaffiliated Voters

In this system, unaffiliated voters can choose to participate in any party primary they want to vote in, but voters affiliated with other parties may not cross over. This system differs from a true open primary because a Democrat cannot cross over and vote in a Republican party primary, or vice versa.

States With Open to Unaffiliated Voters Primaries

States and contests classified as Open to Unaffiliated Voters
StatePrimary election contests
ArizonaDemocratic state ; Republican state
ColoradoDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
LouisianaDemocratic congressional ; Republican congressional ; Democratic state covered offices ; Republican state covered offices
MaineDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
MassachusettsDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
New HampshireDemocratic state ; Democratic presidential ; Republican state ; Republican presidential
New MexicoDemocratic state ; Democratic presidential ; Republican state ; Republican presidential
North CarolinaDemocratic state ; Democratic presidential ; Republican presidential ; Republican state
Rhode IslandDemocratic state ; Republican state ; Democratic presidential ; Republican presidential

All-Comers Primaries

An all-comers primary lists all candidates for an office on the same ballot, regardless of party. All eligible voters may vote in the election, and a candidate who receives the required majority can win outright; otherwise the top candidates advance to a runoff or general election under state law.

States With All-comers Primaries

States and contests classified as All-comers
StatePrimary election contests
LouisianaDemocratic state ; Republican state

Nonpartisan Primaries

A nonpartisan primary does not nominate candidates by political party. Candidates appear without party nomination, and the primary narrows the field for the general election under state law.

States With Nonpartisan Primaries

States and contests classified as Nonpartisan
StatePrimary election contests
NebraskaNonpartisan state legislature

Top-Two Primaries

The “top two” system uses a common ballot, listing all candidates on the same ballot. The top two vote getters in each race, regardless of party, advance to the general election.

States With Top-two Primaries

States and contests classified as Top-two
StatePrimary election contests
CaliforniaDemocratic state ; Republican state
WashingtonDemocratic state ; Republican state

Top-Four Primaries

The "Top four" system is used to determine the top four vote getters that will advance to the General Election, regardless of political affiliation. In accordance with state’s laws, a primary election candidate does not have to be a member of a political party or a political group, to run for office.

States With Top-four Primaries

States and contests classified as Top-four
StatePrimary election contests
AlaskaDemocratic state ; Republican state

About These Rules

This page contains primary election rules and presidential primary delegate allocation information for states and U.S. territories. Primary voting rules and delegate allocation usually apply to statewide partisan primary elections. Check with your local election office for current guidance because rules, dates, and party procedures can change.