Primary Elections Explained

In 2024, 367 of 435 House seats were decided by 10 or more points. In those districts, the general election was a formality. The primary was the real contest. Only 21% of eligible voters showed up.

What is a primary election?

A primary election is the vote that narrows the field before November. In most states, each party holds a primary to choose its nominee, and the winners face each other in the general election.

Primaries exist because parties used to pick candidates in closed-door conventions. Progressive-era reformers in the early 1900s pushed states to let voters choose instead. Today every state holds some form of primary, but the rules vary widely.

What separates one state’s primary from another is who gets to vote in it.

84%
of House seats noncompetitive in 2024
21%
of eligible voters in 2022 midterm primaries
37
seats decided by fewer than 5 points
50
different primary systems across states

Why primaries matter more than generals in safe districts

FairVote found that 367 of 435 House seats in 2024 were decided by 10 or more points or were uncontested. Only 37 seats were decided by fewer than 5 points. In those 367 districts, the general election confirmed what the primary already decided.

Gerrymandering builds those safe districts. When district lines are drawn to guarantee one party wins, the only competitive election is the primary. The nominee of the dominant party wins the general almost automatically. FairVote projected 81% of House seats as already safe for one party a year and a half before the 2026 election.

Most House seats are settled in the primary, not in November.

How Many House Seats Were Competitive in 2024
How Many House Seats Were Competitive in 2024
CategoryValue
Won by 10+ pts or uncontested367
Won by 5-10 pts31
Won by fewer than 5 pts37

Source: FairVote, Dubious Democracy 2024. 367 seats were effectively decided before the general election.

A small number of primary voters in safe districts end up with more say over who represents you in Congress than the much larger November electorate.

In a safe district, whoever wins the primary wins the seat. The November ballot only confirms it.

Types of primary elections

Every state sets its own primary rules. The biggest difference is who can participate.

Primary Election Systems

TypeWho votesStates using it
ClosedOnly registered party members. You must affiliate before the deadline.CT, DE, FL, KY, MD, NV, NJ, NM, NY, OR, PA, WY
Semi-closedParty members plus unaffiliated voters (who may choose a party at the polls).AZ, CO, KS, MA, ME, NC, NH, NJ, OH, RI, UT, WV
OpenAny registered voter, regardless of party. No affiliation required.AL, AR, GA, HI, IL, IN, MI, MN, MO, MS, MT, ND, OH, SC, TN, TX, VA, VT, WI
Top-twoAll candidates on one ballot. Top two advance regardless of party. Two members of the same party can face each other in November.CA, WA
Top-four / nonpartisanAll candidates on one ballot. Top four (or five) advance to ranked-choice general.AK, NE (some offices)

The distinction matters. In closed-primary states, unaffiliated voters, the fastest-growing group in American politics, are locked out of the election that matters most. In Kentucky, you must change your party registration 139 days before the primary. In Connecticut, the deadline is one day before.

Why this creates a representation problem

Closed primaries in safe districts mean a small fraction of party-registered voters choose the representative for the entire district. Everyone else, independents, members of the other party, people who missed the registration deadline, has no meaningful vote.

How primaries work in your state

50-State Primary Systems and Rules

StateTypeIndependents vote?Affiliation deadline
AlabamaOpenYesNone required
AlaskaTop-four nonpartisanYesNone required
ArizonaSemi-closedUnaffiliated may choose29 days before
ArkansasOpenYesNone required
CaliforniaTop-twoYesNone required
ColoradoSemi-closedUnaffiliated may chooseElection day
ConnecticutClosedNo (unless newly registered)1 day before
DelawareClosedNo60 days before general
FloridaClosedNo29 days before
GeorgiaOpenYesNone required
HawaiiOpenYesNone required
IdahoOpen (D) / Closed (R)Varies by partyElection day (D)
IllinoisOpenYesNone required
IndianaOpenYesNone required
IowaSemi-closedUnaffiliated may chooseElection day
KansasSemi-closedUnaffiliated may choose21 days before
KentuckyClosedNo139 days before
LouisianaNonpartisan (jungle)YesNone required
MaineSemi-closedUnaffiliated may chooseElection day
MarylandClosedNo21 days before
MassachusettsSemi-closedUnaffiliated may choose10 days before
MichiganOpenYesNone required
MinnesotaOpenYesNone required
MississippiOpenYesNone required
MissouriOpenYesNone required
MontanaOpenYesNone required
NebraskaSemi-closed (some nonpartisan)VariesVaries by race
NevadaClosedNo14 days before
New HampshireSemi-closedUnaffiliated may chooseElection day
New JerseyClosedNo55 days before
New MexicoClosedNo28 days before
New YorkClosedNoFeb of election year
North CarolinaSemi-closedUnaffiliated may choose25 days before
North DakotaOpenYesNo registration required
OhioSemi-openChoose at pollsElection day
OklahomaSemi-closedUnaffiliated in some25 days before
OregonClosedNo21 days before
PennsylvaniaClosedNo15 days before
Rhode IslandSemi-closedUnaffiliated may choose30 days before
South CarolinaOpenYesNone required
South DakotaSemi-closedUnaffiliated in some15 days before
TennesseeOpenYesNone required
TexasOpenYesNone required
UtahSemi-closedUnaffiliated may choose30 days before
VermontOpenYesNone required
VirginiaOpenYesNone required
WashingtonTop-twoYesNone required
West VirginiaSemi-closedUnaffiliated may choose21 days before
WisconsinOpenYesNone required
WyomingClosedNoElection day

Source: NCSL State Primary Election Types and NCSL Voter Party Affiliation Deadlines. Rules vary by party in some states. Check your state election office for the most current deadlines.

Who shows up for primaries

Turnout collapses in primaries. Barely one in five eligible voters casts a ballot, and the ones who do decide most safe seats.

Midterm primary turnout has not cleared 22% in more than a decade.

Primary vs. General Election Turnout
Primary vs. General Election Turnout
CategoryValue
2010 Midterm18.3%
2014 Midterm14.3%
2018 Midterm19.9%
2022 Midterm21.3%

Percentage of eligible voters who voted in midterm primaries. General election turnout is typically 40-50%. Source: Bipartisan Policy Center.

In 2022, 21.3% of eligible voters cast a ballot in midterm primaries. Compare that to roughly 47% in the 2022 general. Presidential primaries do better, around 29%, but still far below generals.

Primary voters look different from the rest of the electorate

Brookings found that primary voters are older, wealthier, and more ideologically committed than general-election voters. Young voters and lower-income voters are underrepresented in every primary system, though nonpartisan primaries narrow the gap.

Turnout by Primary System Type (2022)

SystemAverage turnoutDifference from closed
Nonpartisan / top-two24.5%+3.8 pts
Open21.9%+1.2 pts
Semi-open / semi-closed21.5%+0.8 pts
Closed20.7%Baseline

Open and nonpartisan systems bring in more voters, but the difference is modest. The bigger driver of low turnout is that most people do not know when their primary is, what it decides, or whether they can participate.

2026 Primary Election Calendar

Primary dates range from March to September. Early primaries set the narrative. Late primaries can leave voters less time to learn about candidates.

2026 State Primary Dates

MonthStates
March 3Texas
AprilWisconsin (April 7)
MayIndiana, Nebraska, North Carolina, Ohio, Oregon, Pennsylvania, West Virginia
JuneAlabama, Arkansas, California, Georgia, Idaho, Iowa, Kentucky, Maine, Mississippi, Montana, Nevada, New Jersey, New Mexico, North Dakota, South Carolina, South Dakota, Virginia
JulyColorado, Maryland, Oklahoma, Utah
AugustArizona, Connecticut, Florida, Hawaii, Kansas, Michigan, Minnesota, Missouri, Tennessee, Vermont, Washington, Wyoming
SeptemberAlaska, Delaware, Louisiana, Massachusetts, New Hampshire, New York, Rhode Island

Source: NCSL 2026 State Primary Election Dates. Some dates are subject to change. Check your state election office for confirmed dates and registration deadlines.

If your state has a closed or semi-closed primary, registration and party-change deadlines may be weeks or months before the primary date. Register or update your registration at vote.gov.

Primary reform stalled after 2024

For a few years the momentum ran toward opening primaries up. Alaska adopted a nonpartisan top-four primary in 2020, and Colorado let unaffiliated voters into party primaries. The 2024 election reversed that momentum.

Voters in five states rejected measures to open their primaries or add ranked-choice voting that November. Nevada turned down the same top-five open primary it had narrowly approved in 2022, which stopped the change from taking effect. Alaska’s top-four system survived a repeal effort by 664 votes out of more than 340,000 cast.

2024 Primary Reform Ballot Measures

StateWhat it proposedResult
NevadaTop-five open primary with ranked-choice general (Question 3)Rejected (had passed in 2022)
ColoradoOpen primary with ranked-choice general (Prop 131)Rejected
IdahoOpen primary with ranked-choice general (Prop 1)Rejected
ArizonaSingle open primary for all candidates (Prop 140)Rejected
South DakotaTop-two open primary (Amendment H)Rejected
AlaskaRepeal the 2020 top-four primary (Measure 2)Failed, system kept by 664 votes

Source: Ballotpedia 2024 Electoral System Ballot Measure Results.

A second wave pushed the opposite way. As of March 2026, 19 states have banned ranked-choice voting outright, with Indiana and Ohio the most recent. Those bans close off the top-four and top-five models that pair an open primary with a ranked-choice general. In much of the country, the partisan primary, open or closed, is now locked in.

What open primaries do and do not fix

Opening a primary is not the same as making a race competitive. An open primary lets more people vote, but where one party dominates a district, the winner still comes from that party. Turnout and gerrymandering are separate problems, and fixing one does not fix the other.

More turnout does not always produce more moderate winners. California and Washington both use a top-two primary, and the moderating effect reformers predicted has been smaller than they hoped.

Ranked-choice voting and open primaries are not the same reform, though the 2024 ballot measures usually bundled them. A state can open its primary without ranking candidates, and it can rank without opening. Voters who rejected the combined packages were not necessarily rejecting either piece on its own.

Closed primaries are not always the barrier they look like. In a genuinely competitive district, independents still get a real vote in November. The lockout bites hardest where one party already holds the seat, which is most of the map.

Frequently asked questions

What is the difference between a primary and a caucus? A primary is a state-run election with secret ballots at polling places. A caucus is a party-run meeting where supporters gather in person to pick a candidate. Most states use primaries now. A few, including Iowa and Wyoming, still run caucuses for some contests.

What is a runoff primary? Some states require the winner to clear 50%. When no candidate does, the top two meet again weeks later in a runoff. Texas holds its 2026 primary runoff on May 26. Georgia, Alabama, and several other Southern states use runoffs too.

Can I vote in both parties’ primaries in the same election? No. In a partisan primary you choose one party’s ballot for that election, even in open-primary states. You cannot vote in the Democratic primary for one office and the Republican primary for another on the same day.

What you can do

  1. Find your primary date and registration deadline. Check the 2026 primary calendar and your voter registration status at vote.gov.
  2. Register with a party if your state requires it. In closed-primary states, unaffiliated voters cannot participate. Some deadlines are months away. Kentucky: 139 days. New York: February of election year.
  3. Vote in your primary. In safe districts, the primary is the election. Skipping it means someone else picks your representative.
  4. Tell someone else. Most people do not know when their primary is. Share the date. The single biggest barrier to primary turnout is not knowing it is happening.
  5. Support primary reform. Open primaries and nonpartisan systems bring in more voters. Represent.Us and Unite America work on primary reform at the state level.

Read the gerrymandering explainer to understand why so many districts are safe. Read the Election 2026 series for what is at stake this cycle. Check your state page for local races and issues.