Primary Threshold

A primary threshold is a vote-share cutoff applied within a party's nomination contest. Depending on the jurisdiction and party rules, crossing the threshold may be required to (1) be awarded any pledged delegates, (2) avoid a runoff primary, or (3) be declared the outright nominee. Thresholds are designed to filter out fringe candidates, concentrate delegate allocation among viable contenders, and reduce the cost and complexity of multi-round contests.

In the United States, the Democratic National Committee requires candidates to receive at least 15% of the vote — either statewide or in a congressional district — to receive pledged delegates from that contest. This 15% viability threshold has been a fixture of Democratic delegate-selection rules across recent presidential cycles and shaped strategic decisions in the 2020 and 2024 primaries, particularly around when lower-polling candidates dropped out. The Republican National Committee allows state parties wider latitude; many Republican state contests use thresholds in the 10–20% range, while others operate as winner-take-all or winner-take-most.

Several U.S. states also impose runoff thresholds in party primaries for state and federal office. Georgia, for example, requires a candidate to win a majority (50% + 1) in a primary to avoid a runoff against the second-place finisher. Other Southern states have historically used similar majority rules, though the specific percentages and offices covered vary.

Outside the U.S., "primary threshold" is sometimes used loosely to describe minimum support rules in party leadership contests, such as the Conservative Party and Labour Party in the UK, where MPs must secure a set number of nominations or a minimum percentage in early ballots to remain on the next round.

Thresholds should not be confused with electoral thresholds in general elections (e.g., the 5% bar for Bundestag representation), which govern access to a legislature rather than nomination within a party.