A jungle primary is an election system where all candidates, regardless of their political party, run on a single ballot, and voters can cast a ballot for any candidate. Depending on the specific state rules, the top finishers (usually the top two) advance to the general election, even if they belong to the same political party.

Officially known as a nonpartisan blanket primary, this system differs significantly from traditional closed or open primaries. Instead of political parties choosing their own nominees to face off in November, a jungle primary lets voters choose from the entire field of candidates upfront.

Understanding how a jungle primary works requires looking at its mechanics, its impact on political campaigns, and the unique strategies candidates use to survive them.

How a Jungle Primary Works: Step-by-Step #

In a traditional primary system, political parties hold separate elections. Registered Democrats vote on a Democratic ballot, registered Republicans vote on a Republican ballot, and third-party or independent voters are often left out or restricted in how they can participate.

The jungle primary completely upends this structure. Here is how the process unfolds:

1. A Single, Unified Ballot: On primary election day, every voter receives the exact same ballot. This ballot lists every single candidate running for a given office—Democrats, Republicans, Libertarians, Green Party members, and Independents—all grouped together under the office they are seeking.
2. Unrestricted Voting: Voters are not restricted by party registration. A voter registered as a Republican can vote for a Democratic candidate for Governor, a Republican candidate for the U.S. Senate, and a Green Party candidate for the House of Representatives all on the same ballot.
3. The Votes Are Tallied: Once the polls close, all votes are pooled and counted together.
4. Advancement to the General Election: The candidates who receive the highest number of votes advance to the general election in November. In a “Top-Two” system, only the first-place and second-place finishers move on, regardless of their party affiliation or what percentage of the total vote they received.

This setup means that a general election ballot in November could feature a matchup between two Democrats, two Republicans, or a major-party candidate and a third-party candidate.

The Different Types of Jungle Primaries #

Not all blanket or “jungle” primaries are identical. Several states have adopted variations of this system to suit their specific legislative goals.

The Top-Two Primary (California and Washington) #

California and Washington are the most prominent states utilizing the traditional Top-Two primary system for statewide and congressional offices. In these states, the top two vote-getters in the primary advance to the general election.

Even if one candidate wins a massive landslide in the primary (for example, securing 65% of the vote), they do not win the office outright. They must still face the second-place finisher (who might have only received 15% of the vote) in the November general election. Because of this, it is common to see highly competitive races between two members of the same party in November. To see how these unique dynamics play out in real-time, you can check the latest polling numbers using comprehensive polling data to track same-party matchups.

The Cajun Primary (Louisiana) #

Louisiana pioneered its own version of the blanket primary, often colloquially called the “Cajun primary.” Unlike California and Washington, Louisiana holds its primary election on the national General Election Day in November.

If a candidate wins a majority (more than 50%) of the vote in this November election, they are declared the winner outright, and no further election is held. However, if no candidate secures a majority, the top two vote-getters advance to a runoff election held in December to determine the winner.

The Top-Four Primary (Alaska) #

Alaska implemented a “Top-Four” primary system starting in 2022. Under this system, all candidates run on a single primary ballot, and the top four finishers advance to the general election.

In the November general election, voters use Ranked-Choice Voting (RCV) to select their preferred candidate among the four survivors. This hybrid model combines the open access of a jungle primary with the consensus-building mechanics of ranked-choice voting.

Pros and Cons of the Jungle Primary System #

Proponents and critics have debated the merits of nonpartisan blanket primaries for decades. The system has clear benefits, but it also introduces unique political challenges.

The Advantages #

• Increased Voter Participation: Independent and unaffiliated voters, who are often excluded from closed primary elections, have an equal voice from the very beginning of the electoral process.
• Encouraging Moderation: In heavily partisan districts, candidates in traditional primaries must appeal to their party’s extreme base to win. In a jungle primary, candidates must appeal to a broader, more moderate electorate to build a winning coalition.
• Competitive General Elections: In districts where one political party heavily dominates, a traditional general election is often a mere formality. Under a Top-Two system, two candidates from the dominant party can face off in November, giving voters a meaningful choice between two different platforms or philosophies.

The Disadvantages #

• The “Party Lockout” Effect: If too many candidates from the majority party run in a primary, they can split their party’s vote so thinly that two candidates from the minority party slip into the top two spots.
• Voter Confusion: General election ballots featuring two candidates from the same party can confuse voters who rely on party labels as a shortcut for understanding a candidate’s values.
• Higher Campaign Costs: Candidates must run two full-scale, statewide, or district-wide campaigns—one to survive the primary and another to win the general election. This significantly increases the influence of fundraising and campaign spending.

Strategic Voting and Campaign Tactics #

Because the rules of a jungle primary differ so drastically from traditional primaries, political parties and campaigns have developed sophisticated, sometimes controversial tactics to manipulate the outcome.

Cleansing the Field #

To avoid the dreaded “party lockout,” state party organizations will often pressure weaker candidates to drop out before the primary. By narrowing their field down to one or two strong candidates, a party ensures its vote share is concentrated, guaranteeing a spot in the November general election.

Strategic Boosting (Opponent Selection) #

One of the most common maneuvers in a jungle primary involves a front-runner spending campaign dollars to “boost” a weaker opponent from the opposing party.

For example, if a strong Democratic candidate is guaranteed first place, they might run ads highlighting the conservative credentials of an extreme Republican candidate. The goal is to elevate that Republican into the second-place spot, box out a more moderate, competitive rival from their own party, and secure an easier matchup in the November general election. Because these strategic shifts can happen rapidly, keeping tabs on candidate momentum via prediction-market sentiment tools is a great way to see which candidates are projected to survive the first round.

Frequently Asked Questions #

What is the difference between an open primary and a jungle primary? #

In an open primary, voters do not have to be registered with a political party to vote, but they must still choose one party’s ballot to vote on (e.g., voting only in the Democratic primary or only in the Republican primary). In a jungle primary, there is only one ballot, and voters can mix and match their votes across different political parties for different offices.

Can two candidates from the same political party face each other in the general election? #

Yes. Under a Top-Two jungle primary system (like those in California and Washington), the top two vote-getters advance to the general election regardless of party. If two Democrats or two Republicans receive the most votes in the primary, they will run against each other in November.

Which states currently use a jungle primary system? #

California and Washington use a Top-Two system for most state and federal offices. Louisiana uses a majority-vote blanket primary system, while Alaska uses a Top-Four primary system paired with ranked-choice voting in the general election. Nebraska also uses a nonpartisan Top-Two system, but only for its unicameral state legislature.

Does a jungle primary help moderate or independent candidates? #

The system is designed to favor candidates who can appeal to a broad, moderate coalition, as they do not have to cater exclusively to partisan primary voters. However, independent and third-party candidates often still struggle against the fundraising power and name recognition of major-party candidates, meaning the top two spots are still usually occupied by Democrats and Republicans.